Was I WRONG about COLD Idling?

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In today’s episode, we’re heading back to the chalkboard for a deep dive experiment testing cold idle starts vs. cold driving to heat up engine oil. To get the most accurate results, we logged each date, time, and temperature during testing for a detailed analysis!
But we didn’t stop there! We brought in special guest Lake Speed Jr. to test our oil samples and break down the science behind engine wear. Which method is actually worse for your engine? The results may surprise you!
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[@DavesAutoCenterCenterville]

Use my link drinkag1.com/davesauto to subscribe and save $20 off your first subscription of AG1!

[@stevenpeterson7234]

Clogging EGR or DPF? Those shouldn't even be on any diesel in the first place.

[@MudOilnGears]

We all know you don't really use the stuff...

[@jsigmon57]

Great video! I've been using the space heater in my truck for about 15 years. Works great.

[@ponch19821]

I want to start of saying great video but I'm not a scientist or a mechanic. I'm a trucker with a Inquisitive mind that unfortunately see a huge whole in your testing that leaves your results at best faulty and at worst unintentionally Deceptively bious. Because with out the data point results of the most common way how most people would operate their vehicle of idling for 10-15 mins & then driving. Without that data point of oil analysis. Your results don't show the complete picture and I feel could be considered unintentionally misleading. Would love to see maybe a re-due of this test that also includes the most common way people would operate their vehicle in cold or hot with idling for 10-15mins plus driving. To get a full picture

[@toyota420xp]

Is explanation is definitely why there was fuel in the oil in the Civic 1.5 turbo

[@themotoroilgeek]

Thanks for letting me help out! This is also why hybrids have higher fuel dilution and moisture in the oil issues, especially in cold weather. For those wondering about driving after idling and boiling off the fuel dilution, the oil temperature must exceed 200F to boil off 50% of the Gasoline. Diesel has a much higher distillation temperature, so even driving the truck for 10 minutes would not get the oil hot enough to boil off the diesel.

[@ncliffor]

Great insight. Great data

[@dawood2u]

I wasn't expecting this from you. So you taught this guy how to make that snake oil called Dave's secret sauce. I unsubscribe from your Channel

[@themotoroilgeek]

@@dawood2u I have no involvement with the fuel additive.

[@NarySllim]

@@dawood2u he’s the exact opposite of a snake oil guy, he’s all about giving us knowledge and we should be very thankful for it. Unsubscribing would be silly.

[@dawood2u]

@@NarySllim Dave and him cooked up Dave's sauce, and Dave is promoting his oil analysis business. Dirty business.

[@wingman8447]

I remember the old VW beetle manual. It said “let the car warm up as long as it takes to roll a cigarette”

[@j1j11j]

..."and get it drawing." as I recall.

[@robertmaybeth3434]

You're referring to the John Muir book right? "How to keep your VW alive." A classic of automotive literature. I bought a copy once and I've never owned a VW. I like his style, and he does talk about a bunch of things that apply, or used to apply, to practically any car, like engine oil and valve adjusting.

[@JimBael]

Was in college in upstate New York in 1967. In January normally 30 below. Most nights-32. Couldn’t drive in NY till 18 (drinking age was 18) so my first car was a VW with 170k owned by the local doctor. Bad news - VWs had horrible heater. Good news - the doc had a gas heater that pulled fuel from the tank, ignited it, and the car would be instantly warm. Was very popular with the coeds. VW died and my senior year got an Opal Kadet. It did not like to start. Ended up getting a one burner Coleman stove and a steel plate. Before my first class, I would light the stove, put the plate on top, and shove underneath the oil pan. What we do for love.

[@MrBigBoy4Life]

As long as it takes to roll a cigarette or a joint?

@@robertmaybeth3434 yup his book. I use to check it out from the library all the time as a kid.

[@seedycanuck1739]

I drove the Ice Road from Yellowknife to Ekati mine for 8 years. Start truck, leave Whitehorse, YT drive to Hay River NT. Load Super B with diesel, drive to Yellowknife, then up the Ice to the mine. Truck was only ever shut down when it was time to change oil - every 250 hours. Running 5W30 full Syn. When parked, Cat engines were left at high idle - about 900 RPM. This lasted for 8 or 9 weeks until Ice started to melt and we returned to Whitehorse, Newer trucks with all the sensors, EGR, DEF etc were broke down all the time. My truck had 2 pieces of electronics - the VHF radio and the stereo.

[@BinkaSnail]

There is zero argument for emissions control being good

[@joec880]

@@BinkaSnail Wait...what? Are you saying there is 0 argument for non pollution?

[@clarkstonguy1065]

I bet there is a nice market up there for pre-emissions trucks. It is the Diesel Particulate Filter that really suffers the most with long idle periods as it needs to build high exhaust temperatures to burn out the soot it collects, around 450°C at least and 600°C is much faster. If you idle for a few days the truck only has two choices waste a whole lot of fuel trying to warm up the exhaust (that is where massive oil dilution comes into play) or give up and you will find an overloaded exhaust when you try to drive away.

[@JohnMoses1897]

@@seedycanuck1739 yep, high idle works good. You had an effective "electronic suite. Too bad the "brilliant"🤣 ectopic engineers can't program an ECM for anything but "normal," which is why I believe so many breakdowns happen to the new trucks - just like liberals, the ECM's have been programed to be "overeducated beyond their ability to reason " logic is not a parameter it can process.

[@stevefrazier2214]

@@joec880No such thing as 0 pollution.

[@tylerfb1]

The Society of Automotive Engineers figured out how engines wear many decades ago. The piston rings and the cylinders are the key wear area, because that's why you end up replacing engines. Piston ring/cylinder wear happens most when the engine coolant is below 160 degrees F. It is pretty much negligible above that. The other contributor is engine LOAD not RPM. High LOAD and low TEMP lead to high cylinder/piston ring wear. The remedy: get heat into the engine as quickly as possible before you load it. THAT's why the recommended procedure is to start and idle for maybe a minute to get oil throughout and pressures up, then drive gently (light loading) until the coolant temp is normal. That is the best compromise between heat and use. If you cannot drive gently, you should idle longer and high idle. But what you should really do is get a block heater. That will allow you to drive under high load immediately.

[@DavesAutoCenterCenterville]

I should have had you on the podcast. Good explanation 👨‍🔧

[@tubester4567]

We're talking about a very small amount of fuel in the oil less than 1%. I would like to see the results after 1000 miles. Then you could work out the rate of oil dilution over time. On the flipside, consumers shouldnt have to follow all these specific rules just to keep their engine intact. Diesel engines have been around for 100 years and you could get a million miles out of them until the last 20 years. Now they are blowing up before 100,000 miles. Thats an engineering problem not a consumer problem. imo

[@steveib724]

I would never buy a Ford anyone needs to work with it lease it ft

[@kc360awareness]

@@DavesAutoCenterCentervillewhere is the link to the podcast?

[@jordan9339]

Why do you need to idle for a minute to build oil pressure? Oil pump is coupled with crankshaft. Idling would mean lower pump speed also. It takes few seconds for oil pressure to go up to specified level. Especially with modern multigrade oils that cope much better with cold.

[@DrKnowsMore]

The other problem with this analysis is that most of us don't idle our car for 10 minutes and then shut it off and let it sit. We usually idle for 5 minutes or 10 minutes and then drive. I'd like to see what kind of impact that has.

[@qksilvr73]

See and that's the key. Idle then drive for 15-20 miles. No one idles it and shuts it off and does that 2 more times. I mean come on.

[@JViello]

Shouldn't change anything. The damage was already done. You're just driving off with 40% more fuel in your oil is all. What would be different IMHO is gas engines vs diesel. Much higher waste heat in gas engines.

[@fz671]

​@@JVielloThe fuel dilution should remain higher in a diesel as diesel is an oil and has much higher flash point than gas. Meaning diesel won't evaporate out of your oil when the engine is warm, where gas being far more volatile with a far lower flashpoint can quite possibly evaporate out of the oil to some degree.

[@noahglenn8305]

Same. I bet most of the volatiles burn off once that oil gets over 200 degrees. Also, the least he could have done is turn on high idle. If you own a diesel truck and it doesn’t have high idle, and it has low oil pressure at idle, get rid of it and get a real diesel truck. He low idled it ON PURPOSE so it would have low oil pressure, more cylinder wash, more fuel in oil, just to prove his point. Except none of us that care about our trucks would do that.

[@benjaminlewis671]

With Science sometimes you are just trying to prove one thing at a time. If he drove it, he may not get such discernment. He was just trying to prove a concept. His hypothesis was true. His null hypothesis was false. This will correlate with oil intervals, so we learn how this experiment has impacts on other factors such as engine and ring life.

[@bushwriter]

Another consideration here is to change your oil as soon as things warm up. In the winter we are going to find our vehicles iced over and needing to thaw out before you can move, which makes idling necessary. Don't wait for the mileage. Just change it when things warm up.

[@arthefuture]

Great point!

[@joshmanis9860]

Also check your owners manual for proper winter oil weight. Standard oil for a Briggs and Stratton is 10w-30 for temps between 0-100F but below 0 they recommend 5w30. Or for use in all temps they recommend 5w30 synthetic

[@RealityGutPunch]

I live in Alberta, Canada. This is what I do. There's always a bit of fuel in the oil after a cold winter, and it's got more contaminants in it than the warm months. I always run synthetic.

[@jjolynyk1232]

How the heck are You only doing 1 Oil change in winter lol I end up doing 2 sometimes 3 if it works out that way and that’s going off miles

[@perlindstrom8676]

Get a electric cabin heater. I have both cabin heater and block heater.

[@errbodyknowsdarules]

Allow me to summarize ~25 mins. Start your cold vehicle, drive it with a soft foot until it comes up to temp.

[@NickFishback]

Yeah, it's winter time, I'm not driving my car/truck until that thermostat opens and starts putting out heat in the interior LMAO. I'll accept the consequences of my actions whenever they come

[@3hree6ix94]

Same plus how tf ya post to drive with frost or snow on the weind sheilf​@@NickFishback

[@GOD719]

@@NickFishback I got a space heater, wifi plug, and an extension cord. I had it set for a specific time to turn on and off. That way. The cab would be warm without running the truck. But now i have a remote start and my ram puts out extremely hot air. like 190 degrees from the vents.

[@vancelyndon3416]

@@3hree6ix94-answer to that is simple. 1) Freeze you ass off like Dave did scraping the windshield. 2) find a long drop cord. 3) plug in $30 space heater in said $100k truck. 4) hope it doesn’t trip over and melt the interior. 5) should have been #1 - leave yourself 30 mins extra time in the morning for this process.

[@hanselito2416]

that sounds about correct asf.+

[@GaryL3803]

My Dad, a aircraft/automobile mechanic, advised 2secs of idle for each 10 degrees below 100 degrees plus an additional 2 degrees and easy on the throttle for the first mile. This has worked well for me.

[@Ozgrade3]

It's Saturday afternoon, on a hot summers day here in Australia. The lawns are done, chores are all done. The afternoon is all mine. I couldn't think of a better way to spend it than watching two highly knowledgeable guys talking about oil temperature.

[@BowensBlvd]

cheers from Michigan enduring winter and it's 1230 am

[@rayhuggart5214]

@@Ozgrade3 lol

[@alechappy2070]

Which in QLD is 25C or 77F sitting in the garage... Oh and no salt, no rust... We drive them 300,000 until the aboriginals say Bro I give you $500 and a full Coraki hand bag for that pristine Falcon Bro.

[@sonicrulez]

literally a man's dream

[@slalomking]

We are coming to Australia this Oct to see your great country!!! What temps will it be then, in the Outback?

[@myvideosrockthehouse]

In europe they had a webasto option on many diesels. It's a small and efficient diesel heater that warms up the coolant. Once the coolant is warm, the electrical coolant pump activated with the heater fan. When you get in and start, the motor is warm and so is the interior. The diesel webasto is superior as it can yield more heat then electric heaters which are limited in current. Once we start valuing long term usability in our environmental equations, the polluting webasti option will make a lot of sense.

[@Salmon_Rush_Die]

Webasto = awesome.

[@fredrikgustafsson8]

Yes my scania v8 is always warm in the morning and 24°c in the cab....👌💪

[@TEC_Stuff]

Mercedes Sprinter vans here in the U.S. have this option, my dad’s 2021 van is optioned this way and he loves the feature. It is nearly instant heat for the cabin.

[@stuntvist]

@@fredrikgustafsson8 Well in most Euro semis you can set it on a clock to turn the heater on when you're away from the truck so you basically never have to do a proper cold start if you use the functions provided to you. Can set it to come on an hour before you come into work on Monday instead of running it all weekend. Much nicer than the old stuff where you have to be present in the cab to turn on or off the coolant heater.

[@matthewmcdaniel8432]

Great video! I am a firm believer in starting My car, plug phone in, put seatbelt on, then going once my idle rpms drop at least once. Then gently drive like normal, you'll save a ton of gas too, and I get 44 combined lifetime over 22k miles. Car runs like a top, no gas smell when I change the oil, and I live in Michigan. 2024 Honda Civic 2.0 NA engine. 5k oil changes

[@leecowell8165]

Hopefully you changed that oil first time around 500 miles? Wouldn't be a terrible idea to change it the 2nd time around 2k miles either.

[@samjones4772]

This is more a diesel argument tbh

[@thegonz7833]

Hats off to Jr. highly respected. A+ for Dave making his point. Daves goals, clearly are to help the folks make their autos last.

[@georgehofgren6123]

@thegonz7833 Clearly you don't recognize the "advice" of an industry-leading ENGINE REBUILDER. How much do you think his business relies upon Head Gasket work and cracked exhaust maifolds....? If you knew how bad it is for your frozen block to drive at all until a little warm, you'd take this "advice" as practically Sinister. Now cut to the next holiday clip where he and his wife pray for your success in life 🙏 😉🤪😂🤣🤣

[@russsalvage3155]

Worked on fleet of log trucks 50 years ago. Cummins engineers gave same advice then. Start the engine, let it idle a minute so the gears in engine snd transmission had a good film and roll out easy.

[@shawnkelly695]

Good luck when cant see. Windows covered in ice. Even if no ice when you get into ice cold vehicle your breath fogs the windows up. Yall sound like florida folk that never see the cold

[@rescuesar54]

Exactly! I was a mechanic in the military way back…we’d only give a few minutes to warm up then roll out…but never ten minutes! M1 Abrams needed a little longer…

[@shawnkelly695]

@rescuesar54 lol dont do that in minus 40.

[@Billy97ify]

@@shawnkelly695 That is what a window scraper is for.

[@rescuesar54]

@@shawnkelly695 yeah, yeah, yeah…it gets cold in northwest Wyoming too…never had a problem. Systems will warm up faster if you slow roll and do a light load the first five minutes…absolutely no need to let it idle for five-ten minutes even with -40 it’s wasteful and unnecessary…but you do you and keep perpetuating the myth…I won’t!

[@Ocboy420]

Lake is the man when it comes to engines & oil

[@jwbranham2009]

Lakespeed and Dave make a great team for educating folks like me. I absolutely love your work and appreciate the leadership you demostrate in your videos.

[@davidadkison4702]

My Dad was a semi truck driver and when very cold weather he would go out and start the truck and let it idle until the exhaust stopped blowing blue smoke and started to turn black like it should. He then would drive off

[@rayhuggart5214]

@@davidadkison4702 yep that's how I do it

[@rayhuggart5214]

@@davidadkison4702 that's jow I do it

[@simonmears1726]

Blue smoke on start up valve guide seals not sealing correct

[@reloadnorth7722]

Well, where I live in North East Ontario Canada it has already gone to -51 with windchill. Even with block heaters, I am letting my vehicle warm up a min of 5 minutes, most likely 10.

[@loudawg907]

Yes, otherwise it won’t start then you’ll be driving in a damn ice block. I live in Alaska and it gets very cold here.

[@reloadnorth7722]

@@loudawg907 Stay safe and warm.

[@GOD719]

I have a space heater, wifi plug, and extension cord. Put it in your truck. It will warm the cab and defrost the windows. The wifi plug is set for a certain time to turn on and off. So you don't worry about your truck burning lol

[@NajaNigricolis55]

Do you drive a diesel though?

[@Jacob1986]

@@GOD719that is risky

[@mikenicholson2548]

Sounds great in science. You need to test your theory with block heaters and oil heaters. Also, I live on a highway. If I let my truck idol for two minutes and pull out and gently drive it, someone will crash into me. So, I am going to test your theory on my 6.4. This weekend, I am due for an oil change. I will plug my truck in and let Idol for ten minutes and go drive it like I always do. Then I will do your idea. Send both oil samples into the lab I use for my semi. One thing also with diesels is that they need to be run at highway speeds, not an in town driver. I will send you my results. You can do what you want, and I am not saying you're wrong or right, but I get 800000 to a million miles out of my semis engines with a lot of idol time.

[@1shakezula1]

I live in northern Minnesota where low temps are well below zero for much of the winter, and I can tell you that there's a big difference between 28 degrees and 28 degrees below zero. I agree that it's just fine to start driving immediately when the temps are just below freezing, but when you get well below zero it's quite apparent that the car does NOT like being asked to move. Maybe you'll get more fuel in the oil, but based on how the vehicle drives I can say that it appreciates being given 10 minutes to warm a little before actually moving. I'd be curious to see the results of this experiment when temps are 40-50 degrees colder (both fuel content and wear metals).

[@BinkaSnail]

Agree

[@mudlovr]

I live in northern ontario 18 ram g56 diesel it idles long enough for oil temp to start registering ill never agree with extended idling

[@zachgunnink6136]

agree. I thought it was funny when he said its so cold out you can barelt stand it. Then he shows a thermometer where its like 30 degrees above. A little different when it gets to -15 F for a daily high.

[@quentonsmith6085]

I’m in Fairbanks. You cold start at -40 and start driving stuff WILL break. Hell 10 or above I’m driving.

[@alternatemusicaddict5226]

dude what kind of analogy is that. there's a big difference between 28,18 degrees?? 28 to -28?? thats a 56 degree change ?? thats like saying theres a big difference between 28 and 84 degrees ??

[@JustinKingOffroad]

running 10w-30 on a truck that is mostly parked inside, running regens etc, but has 1 or 2 times a month where it is outside overnight in the winter, i usually let my temps climb to 100 degrees before i really get going (that's 10-15 minutes of idling), my total fuel dilution over 5000 miles was under 0.5% so i'm gonna just go ahead and keep letting my vehicle warm up to what I am comfortable with before taking off. proof is in my oil analysis that i'm not doing anything wrong.

[@stco2426]

Innteresting to see 0.45% fuel dilution after 3 cold starts and 10 min driving, albeit this is best practise. Just goes to show that all cold starts include a little bit of oil punishment. Been a big advocate of getting the oil moving then getting the vehicle moving soon afterwards and this shows it nicely. Excellent and thanks for making and sharing.

[@carllarsen2769]

You always say to don't put a load on it till it warms up, but a lot of people that drive diesels pull trailers daily.

[@CrAZyFr33Rid3r]

He means use, for instance, less than half throttle until its warm

[@100pyatt]

Light load is the key, not hammering on it whatsoever

[@tylerfb1]

Block heater is your best bet, then.

[@KDlGG]

@@100pyattlight load aka in gear at best.

[@WyFoster]

Fuel dilution will be remedied once the oil heats all the way up and boils off the fuel. Cold oil and water, not great for bearings or piston rings if you're going straight to a high load scenario like that.

[@Sean-b1t]

isn’t the expectation that you’ll go and drive the car/truck after letting it idle? No one is just going to idle their engine for 10 minutes a couple times a day then shut it off. If I let the engine idle from cold start for 10 minutes, then drive it on the highway for an hour, isn’t that going to burn off all of the contaminants? I think the whole reason people think it’s a good idea to idle their engines on cold start is to prevent the engine from hitting high loads with cold oil, as cold oil has lower lubrication properties. People aren’t idling to prevent oil contamination, because the expectation is that they’ll burn it off through normal driving. I’d be interested to see a comparison in cylinder wall wear between the idle test and the drive test. I don’t care what anyone says, even going half throttle on a cold engine is a terrible feeling.

[@Sixpointtwoliter]

The point is that you let it sit for 10 minutes to warm up everyday over its life. Where the fuel dumped oil is lubricating the engine, and that little by little that 10 minutes of poor lubrication over and over matters. Versus just driving and always avoiding that problem in the first place. He's just showing you what happens as it sits

[@overworked30]

Came here to say the same thing. Who idles for 10 minutes and turns off their car

[@drivewayhero]

Papers show that the most wear occurs when your coolant temp is low. The faster you bring it up thr less wear there will be. So idling it long time brings it up slower than driving it, resulting in more wear.

[@lbrnj1994]

That fuels still in the crankcase after driving it after the 10 min idle time. And yes it burns it off once the oil temps gets high enough. But after how long of being in the oil does the fuel finally burn off vs driving it right away doesn't even put the fuel in the oil in the first place

[@HelplmAlive]

I agree. But I do know some people with diesel trucks that actually start it up every so often without driving for whatever reason.

[@mikeafa1]

Dave i think you forgot one other test... Idle for 10 min, then drive for 10 or 15 minutes, three times. I think you will see your fuel dilution drop a lot. This is pretty much the scenario for my wife and i in NY when its really cold, below 30 degrees. Above that we olny idle for less than one or two minuites. I had Blackstone labs do my oil testing last month for a 2018 Ford Expedition V6 and a 2013 Chrysler 300S V6 and there was 1% or less fuel in the oil. Your thoughts Dave?

[@Jonathan-hx6oy]

Comparing apples and oranges. Gas burner with alot lower evap temp than diesel.

[@JViello]

Gas engine. Different beast. They should have mentioned that in the video for folks who don't know the differences in engine mechanics between the two.

[@j3tt436]

@@Jonathan-hx6oyI think there could be a question of the extra fuel stacking in the cylinders from short multiple short idling periods that weren’t burnt off in the usual drive after Maybe?

[@austin2314]

I agree with the practice the data supports, but feel like the numbers need to be put into a bit of perspective. The fuel dilution numbers were 0.77% and 0.45%. If the engine takes 13 quarts of oil, we're talking about 3.2 ounces of fuel vs 1.9 ounces of fuel. I'm just not convinced fuel dilution is the variable that most strongly supports the argument.

[@jeffs2809]

It was only 3 starts. How many 10-15 minute warm-ups are going to happen in 3, 5 or 10,000 miles between oil changes? While I think this testing is more indicative of the short trip, grocery getter type of driving effects, it could still be a significant amount of fuel dilution by the time the oil is changed. Possibly a more accurate test would be to drive the vehicle long enough to fully reach operating temperature for each test. In the end, 42% is still a significant difference and could amount to quite a bit more dilution by oil change time.

[@ttrs7907]

Also that was the first oil change after a fuel system catastrophe, how much of that fuel was in the residual oil that doesn’t drain out

[@robertmaybeth3434]

..in this experiment Dave was only counting fuel dilution for ONE start and run! Now multiply your figures by every cold start they have to do in between oil changes. The PCV system is there to at least assist in burning off the fuel dilution - but it's the last thing I'd ever count on to reduce ditto.

[@williammeyer6905]

Ide like to see the test ran backwards. If you do an oil change and run the truck for 30 minutes then change the oil again the second time you change it the oil will be cleaner... that's just facts

[@austin2314]

@@ttrs7907 so true! When you do an oil change, you're not able to remove every quart of oil. There's no way to say any previous fuel dilution was completely cleaned from the engine, unless he completed multiple oil changes prior to the first experiment.

[@LeadStarDude]

When it is extremely cold (below freezing), I let my engine idle up to a couple of minutes. Basically until it starts to idle down from the initial high idle state. As soon as it drops that first 100 rpm I start driving. In fair/cool weather (above freezing up to about 55⁰F), that takes about 20 to 30 seconds. When it's extremely cold that can take up to 2 minutes. Anything beyond that is bad for the engine imo. When it is above 55⁰F I don't wait at all

[@NC-xk1eg]

Total Agreement! 👍

[@Romulan112]

I disagree. I have a 2025 Subaru Outback. When I start it in, say, 20-degree weather, it goes to around 1800 rpm and stays there until it's good and ready to go to 700 rpm. There is no middle ground. There is no gradual lowering of the rpm the warmer it gets. This whole process takes from 4-6 minutes. If I were to do like yourself and just go, the torque convertor along with the CVT would die an early death. You state that when its 55 degrees out you don't wait. You would be getting early transmission replacements. You can't just slam it into drive at high rpms. The transmission cost more than a replacement engine.

[@tdotw77]

@Romulan112...The engine Idle drops down when you apply the brakes in most vehicles

[@Engineersoldinterstingstuff]

Basically start it up let the oil get circulating, 10 sec, then start driving tha car with minimum load. Have alwaya done this, 35 years in Sweden. Change oil often.

[@MrShadow1617]

@@Engineersoldinterstingstuff This video and the people here are talking about cars with CVT/automatic transmissions, its a little bit different with manual I think.

[@jameslandi4688]

Solid information....remote start fobs time out at 10 minutes, and there are comments on the internet about ' why isn't my cab warm after a ten minute remote start?'

[@gilianrampart8514]

Mine is warm!

[@rcrepps3949]

​@gilianrampart8514 in Minnesota when it's -45° my truck isn't warm. But in Southern Mississippi, when it's 32° my truck is warm.

[@gilianrampart8514]

@rcrepps3949 You may want a block heater! My Alaskan truck had one, and it worked great

[@gilianrampart8514]

@@rcrepps3949 A 50/50 mixture of water and antifreeze freezes at around -35°F

[@gamerincorporated154]

Naw, mine time out at 36 min, but its an aftermarket. Although i don't let it idle that long. But after about 8 or 9 min, its comfortable. Its not 'warm' but its not freezing cold air either

[@MrRebar15]

*Dave's Auto Center* Bravo well done, thank-you gentlemen for taking the time to bring us along on this study. GOD Bless.

[@cj3518]

My 04 dodge has 800,000 miles on it and so far have never touched the engine. I change oil every 10,000 miles and also only use Mobil delvac 1300. I have only 2 or 3 times ever had to add a quart of oil between oil changes. This truck pulls campers for a living. 2 to 3 times a week it idles cold for 10-20 minutes. When I’m pulling a trailer this truck never shuts off until I’m home. My point is, if cold idling was so detrimental to the engine I should be rebuilding mine every year. I understand people think these gentlemen are the elites to listen too but I would challenge their real world knowledge of people who work these diesels everyday and not just own them for picking up groceries. I spent 30 years working for a commercial farming business. I ran a lot of different equipment. We idled everything when it was cold. I can honestly say in those 30 years we never had any engine failures or any engines with excessive oil consumption. I’m sure their tests are accurate and I’m not debating that there is more fuel dilution idling cold, I’m sure there is but is it enough to worry about? In my case apparently not but if your sole purpose of owning a diesel pickup is just to drive to work and back and not for doing work then I would probably agree you should plug your trucks in when below 50 and start and go but as for the person that actually works the truck everyday all day I don’t think it matters.

[@46fd04]

Great test! One thing that would help even more for diesel engines is covering the grill (during the cold winter season). RAM trucks with Cummins diesel engines come with a winter grill cover which I use every year in Ontario Canada. My coolant & engine temps come up very quickly. I rarely see the Cummins RAMS covered up in the winter, and yet the winter cover comes stock with every truck.

[@markmitchell538]

superb inquiry!!! In New Mexico, I run a 1989 Honda CRX HF as my daily driver. I have used a Honda OEM engine block heater year round for 25 years. I also drive off gently after 20 seconds. So far, I have well over 300k miles on the original engine. Still gets 54 MPG in town, 61 on the road. I thought the piston ring gap vs temp might be an issue. This systematic experiment confirms my suspicions. This is why I watch Dave's videos!!!!!

[@jeffm5099]

Lol you're not getting 60mpg in a CRX, sorry.

[@Salmon_Rush_Die]

@@jeffm5099 Maybe he drives everywhere at 35 mph & 45 on the highway

[@tdotw77]

🤔 Km\ph*👌🏻

[@chrisstromberg6527]

Love this content Dave, excellent! This is why I listen to an engine rebuilder when I need expert advice on engines, this is why I listen to my doctor when I need expert advice on my health, this is why I listen to my accountant when I need expert advice on my financials, this is why I listen to the experts! There are so many people out there, relying on the advice given by politicians/social media influencers who are not experts in any given field!

[@dontfit6380]

You should not listen to your doctor on health advise. They no nothing of health. They only know how to throw pharmaceuticals at a problem.

[@gstranman9677]

I didn't realize the difference was so great. I know people who idle their trucks and pickups for hours when it's cold like now.

[@miklm]

I believe the results will be different for idle after reaching operating temp. That’s not tested here at all.

[@Resistculturaldecline]

​@miklm Correct. Idling is never a best practice, but idling at operating temp isn't as bad. Oils are up to temp, so low parasitic drag requiring less overall fuel usage. Cylinders/pistons/rings are close to their optimal size. Doesn't take much fuel at all to spin a warm engine, and that lesser amount of fuel is being contained more completely in the cylinders.

[@Stanjara]

0.01 and 0.02 is a 100% difference ... OMG!!!!!!!!!!!!

[@oblioarrow768]

More fuel in the oil is a bad thing. Castrol did an article on this and talked about viscosity changes, additive changes, and oxidation contamination. They also stated that diesel fuel does flash off when engine gets hot but the peak percent of fuel dilution should never exceed 4% as per the standard OEM specifications or you might be affecting the hydrodynamic wedge formed by the oil. Lower viscosity during cold temperatures is desirable due to fuel dilution that corrects itself as the engine heats up and flashes off the fuel. But over time the fuel dilution will affect the engine oil as it approaches 4%. So a hypothesis is this…Therefore it might be wise to let your engine warm up in the winter to take advantage of the affects of lower viscosity due to the fuel dilution but to change your oil more frequently to stay below the 4% mark and remove the buildup affects of fuel dilution on the oil. This is an interesting systems discussion.

[@johndoran3274]

I’ve been starting and immediately driving for decades without any issues. Mainly because of living in a heavily populated area and not wanting to annoy my neighbors. Back in the’80s and early’90s, I had to warm up my big truck, not for the engine, but for the transmission. When it was around zero degrees, you physically couldn’t shift the truck until the gear lube warmed up a little. Now with the synthetic lubes, it’s not an issue at all.

[@blackout7615]

Start it and let it run for the time it takes to scrape all the windows.

[@100pyatt]

Exactly

[@856dbauer]

Laughing at -40....

[@jjolynyk1232]

I just start it and let it run til the windows are clear lol. Not keeping them past warranty ever anyways

[@markcollins457]

Love this fact finding mission. I have been in the HVAC business for 50 years and in my early days I worked mostly on commercial oil fired burners. Oil fired burners have pre-heaters to elevate the oil temperature to enhance combustion efficiency if that heater failed there would be unburnt fuel stuck to the sides of the combustion chamber(soot). There are many other factors involved but the basics are the same. I agree keep that block warm the oil warm and the fuel warm. If you can't put a load on it warm it externally. Great class Dave.

[@gizclifford]

I plug my block heater in every night (on a timer for 3hrs) start up let idle until oil pressure is up then drive. Oil and coolant temp are around 98 degrees.

[@447ephesians6]

I still love to let my truck idle 20 minutes regardless of this new information. This is excellent information and I appreciate the exact science behind the theory and oil testing. I'm from Montana, when my truck is outside at 0 F I need time for the cabin and seats to heat up. 30 seconds is not enough on our freezing days with snow and blizzard winds. Maybe I switch to gasser engines in the F350, rather than diesel motors?

[@100pyatt]

5 minutes worth of idle to allow oil pressure to drop before applying light load and low RPM is plenty good. No need for 20 minute idling sessions

[@throwawaypt2throwawaypt2-xp8nx]

​@@100pyatti need to sit in a warm cabin, u can sit in ur freezer if u wish

[@Jimethia]

It's -40f here today, and be damned if I'll start and drive a vehicle without letting it idle for at least 10 minutes. I do 100% agree that idling lets more fuel past the rings and can cause issue IF you dont calculate that into your oil change intervals. I run absolutely no longer than 5000 miles to an oil change on anything I own. Usually closer to 4000 miles per change. And when there is extended idle time, its ruduced accordingly. Every diesel I've owned has idled accordingly to the temperature and what I see fit. With proper winter fronts and measures done to keep heat in the engine bay. And the lowest mile one I sold was just shy of 300k miles with the only work being done was a single set of injectors. Highest mile unit I own is just over a million miles and its had one set of injectors and a pump and a head gasket job at about 800k miles. Granted they only go up to the mid 2000s for years, but my experience tells me the oil change interval matters more than anything.

[@MattDunbarRiding]

Really would like an engine wear analysis between the two.

[@davidstainton7201]

This very interesting but what about @-30 F? It’s also a consideration regarding transmission temp etc. I still believe that being plugged in and a 10 minute idle is easier on your motor. I’ve seen oil so thick it blew out the oil filter.

[@DavesAutoCenterCenterville]

We go in depth into all of this on the full podcast with Lake Speed, link is in the description 👨‍🔧

[@clarkstonguy1065]

Oil at -30°F is like honey and your oil pump needs to suck it from the oil pan in order to push it through the rest of your motor, let it idle for 2 minutes to make sure you have good oil pressure before driving.

[@JohnSmith-ih9rh]

These videos are great! I feel a little smarter every time I watch one. Mr speed is the best guest you could have. But super Dave is still the man! Keep up the good work and to the crew, y'all guys rock what a team!!

[@tdotw77]

Super Dave Osborne?🤔 😁😄😂🤣

[@danpokojski143]

Really love the fact you are acting as a scientist here and not just a technician. I know the auto/diesel repair environment isn't conducive to this kind of work but it should be. Most techs would love to have the freedom to do this kind of work.

[@jeffreyjones593]

Great job. Really opened my eyes. I’ve let my 2022 F159 with 3.3L warm up several times for 10 minutes trying to get the can warm. Not anymore.

[@JViello]

Gas engines are totally different. I still wouldn't idle for long periods when ice cold, but it's definitely not the same at all. Gas is a different beast.

[@TreatsOnTheStreets]

We idle our diesel for at least 10 minutes every morning in winter. I also do oil analysis on every oil change. I have never had excessive fuel in the oil. Usually it is less than the average. As long as you're driving it to the point that the oil heats up it isn't going to be a problem. Change your oil frequently either way and you'll be fine. As for the DPF, can't speak to that. Isn't that what regen is for?

[@WestsideCritters]

I would suspect that a lot of the fuel burns off after driving it but in mean while excessive fuel has been run through engine creating more wear on cylinder walls !!

[@TreatsOnTheStreets]

@WestsideCritters if that were true then my oil analysis would come back with high iron which hasn't been the case

[@andyc935]

My suspicion is that your oil analysis does not show excessive fuel in the oil because it evaporated after long drives. So, from the results of Dave's experiment, you did at one point have higher amounts of fuel in the oil at the start of your trips, meaning your oil probably was not as effective as it should be in reducing wear during the warmup phase. That is just my guess.

[@TreatsOnTheStreets]

@andyc935 I believe you are correct but the fuel percentage present even before evaporation is so miniscule that it isn't going to meaningfully affect anything. Now, if all you did was idle your car for 10 minutes and turn it off, only to do the same thing the next day, then that could pose a problem after weeks of never getting oil up to temp.

[@deletedcheeto7979]

So my question is....what about high idle as soon as your start it. My LBZ high idle after 1 min of idling

[@MechanicalMercenary]

As Paul Harrel would say is enough difference to make a difference? I have a open intake and exhaust and will continue to high idle for 10 minutes to put the warmth in all my fluids including atf. How much fuel was there? How much oil life are you really losing and can you do summer idling with ac next? Thanks for the science Dave and Lake.

[@jmadison0611]

When you changed the oil the first time, did you totally flush the system one time to ensure that there was no left over oil from in the cooler. That will raise the fuel level in the oil.😊

[@87s15lt1]

THIS!!!

[@espweirdo]

and he had a fuel system failure, so the previous oil was probably very diluted…

[@ttrs7907]

Exactly what I was thinking

[@JohnMoses1897]

Absolutely. 1050 - 1200 rpm high idle 1) all sensors functioning. 2) no vacuum, very little boost from turbo for combustion efficiency. 3) full combustion seals rings to cylinder walls. 4) full oil pressure so everything 100% lubed - this includes undersides of pistons = wrist pins from squirter, both lube & cool. 5) This is what most people forget, smooths out firing impulses so harmonic vibrations are minimized.

[@dougcjohn]

Great Video… always enjoy Oil Geek’s scientific approach. Agree with short idle time, although huge difference in 30 seconds and 10 minutes. For the Engine: rotating components, block expansion: main & cam journals, cam components, etc… the idle time of 2-3 minutes allows engine to slightly warm and torque converter to move fluid through transmission, friction plates, steering pump, etc… slightly warming. Especially using a high idle adjustment. The difference in amount of fuel into engine between 30 seconds and 3 minutes is insignificant, especially if truck is driven long enough to get engine up to operating temp, which helps fuel in oil vaporize a little. When stone cold, the whole truck needs warmed: suspension, axles, shocks, etc… length of gentle drive is also debatable… 1 block, 1 mile, 10 miles? During a gentle drive, the engine isn’t any higher normally than idle… little more load, but you’re rotating drivetrain components. Then on road at 45-65, you’re warming everything up and minimizing fuel into oil. Totally agree, keep idle short especially on new emission engines… but 20-30 seconds is too short for the care of whole truck components. I’ve never idled a truck long to warm up cab… we’re dressed for cold, it’s for the benefit & care of machinery… Ag & Road. Problem has increased for Diesel due to Emissions… AND new diesel Owners treating a diesel like a Gas vehicle. Long Warm up and short drives. Experienced Diesel Owners are tuned into the machinery, treat it like a diesel. Would never start a diesel in cold (or warmth) for a quick 2 minute trip for groceries… take the gas vehicle instead.

[@matthewmashl7154]

The way i see it, it’s more than just fuel in the oil, its also wear on the internal parts. An engine at idle is producing much less power, and in-turn putting less force on internal parts that arent close to tolerances they would be when warm. Driving on a cold engine would put more stress on the rods, crank, and pistons that arent at the tolerances they should be. Letting the engine idle gives them a chance to get some heat in them to get closer, if not to the tolerances they should be at when warm. Im sure there are plenty of people that can still here the chevy piston slap on a cold startup. Anyone who does likely let it idle until it at least went away.

[@Warrior_Resisting_Colonialism]

You still don't get it. The sooner you can get it in and drive, the sooner those internal parts will come up to temp. So you're needlessly increasing the engine ware, by letting it sit there and idle cold. You want to SHORTEN the time the engine is cold, for ALL aspects. This means, start it and drive it easy for 10-15 minutes to help it come up to temp as quickly as you can, THEN once it's up to temp, drive it normally, so you don't harm cold parts.

[@ScooterSafety]

Just install a block heater and oil pan heater. That's what I did.

[@sixpest]

​@@Warrior_Resisting_Colonialism👍 yup

[@aidenp5768]

@@Warrior_Resisting_ColonialismWell you are correct but you introduce another issue, what you stated also depends on distance driven too, if you drive let’s say 15 miles or less that’s not enough time for the engine to burn off fuel like gasoline and contaminates but also water / vapor. So by letting the car idle 5-7 minutes I believe is a good middle ground you give the car a head start on warming up the oil in turn the oil is cleaner potentially by having a better chance at burning any of the elements that ruins the oil besides just fuel. My BMW for example takes at least 15 minutes just to hit the stable 200F which is the temp water and other stuff burns off, if I use the start and go method the car never hits even 180F within 20 miles

[@Warrior_Resisting_Colonialism]

@@aidenp5768 Nothing should be driven like that.

[@peni80085]

For block heaters and interior heaters you should check out a company called Defa. It's a Norwegian brand. Pretty popular here in the Nordic countries.

[@johanlahti84]

yeah or Calix. but I guess they might only make 230V stuff. Not sure tho

[@Watts378]

For gasoline engines, I watched a show here on YT. The findings were, idling your gas car does more wear n tear in cold temps due to the computer adding more fuel and less air in the combustion chamber. Gas is a varnish that can strip oil causing more wear. It was an interesting video.

[@jeffu3248]

Very Interesting 🤔

[@MarkChopping-qm1sq]

Dave's worth his weight in GOLD.... AND MORE. I LOVE MY PRE DEF 97' POWERSTROKE AND MY 92' CUMMINS first gen Dodge. 1990's BEST ENGINES

[@rbnhood39]

It’s so refreshing to see a shop that is passionate about their craft.

[@hoghead4846]

Would love to see a video on recommendations on shutting down a warm engine after working it hard.

[@66balsam]

I give em a 30 second idle before shutting off

[@DavesAutoCenterCenterville]

I'm going to put that on the list for future videos!

[@rivalrepairs]

If driving normally just shut it off. If you were hammering it beforehand turbo could be very hot and burn oil after shutdown so drive slowly for 5 mins before shutoff. Also brakes could be very hot so best to cool them a bit. But you have to be driving like an idiot to have these issues.

[@hoghead4846]

@@rivalrepairs not driving like an idiot just pulling a trailer on a hot day with a 6.7 power stroke.

[@hoghead4846]

@@DavesAutoCenterCenterville Thank you Dave.

[@calmargarita]

Thank you, Dave and LAKE for updating my driving lifestyle. I’ve been a professional diesel jockey for 43 years driving truck. This just makes me shake my head.

[@msumungo]

A great fan of the channel here. I have learned here a lot about American hardware and how to work with it. Greetings from Finland. :)

[@TheMjlover420]

This guy is a legend

[@DavesAutoCenterCenterville]

Thanks for watching from Finland 👍

[@pugbug288]

Lots of good knowledge. I found my 15 F-150 3.5 Ecoboost thins out the oil during winter. I’m sure my remote start, and short trips doesn’t help. I change it at 3000 miles it still lowers it to a 5w-20 from a 5w-30. The wear looked metal looked good but still not good. I’m running a 0w-40 right now.

[@n085fs]

Thank you for the proof of what I told my wife about idling her vehicle for so long before driving. She bought her car, she's proud of her car, she wants it to last as long as possible. But I told her, we live on a hill in a 50km/h zone and you can safely crawl at 20km/h if you want to. The car will warm faster as you fall downhill, still idling, because the oil in the transmission will be moving to warm up too. However, she came back with a great point. From home, sure. She'll just drive easily. But from work, she works at a road that's a speed limit 90km/h. If she gets off work, and immediately drives, she's near flooring the pedal to not get hit by people doing 110 because we all know that not everybody sticks to an exact speed limit. So, from getting out of work, it is better that she lets it idle for ~10 mins.

[@hgauge]

Would this apply to a gas engine?

[@bigdaddymak1439]

Yes just not as extreme because diesel engines warm up slow

[@WASDxMerceless]

Yep

[@rasalas2x]

A fast warm up inside the cab is to purchase the electric auxiliary heater from the factory.

[@HatBilly2008]

In the winter change the oil sooner than in the summer 😊.

[@mikeyschmidt20]

I always appreciate the tests you gentlemen do to help the rest of us out. It is very helpful. Thank you

[@OperationFrigateBird]

Well, I was wrong on this. I have always ascribed to the old school thinking on this to let the engine warm up so the rings will expand before you go driving it and giving it throttle. This was very good to know; thanks for doing this test. I will pass the word around.

[@DavesAutoCenterCenterville]

You are a rare breed. I’m always impressed with humble people like you. Thank you 👨‍🔧

[@OperationFrigateBird]

@@DavesAutoCenterCenterville I grew up around older generations in the midwest. I am in the second half of Gen X. I decided to put all of my effort into getting my mechanical engineering degree. I did well in school. This was after learning how to run reactor plants on Navy submarines. I ended up getting my first engineering job at Electric Boat; they make submarines for the Navy. I learned then that what you just said was absolutely true. I never had any idea how arrogant and fake many/most people are until I worked as an engineer. Everybody was afraid to admit that they were wrong or didn't know something, especially the management. This was true at the other big name companies that I worked for as well, like Pratt and Whitney, for example. Even worse, these people sell out this country on a daily basis. I'm not kidding; my wife still works as an engineer there at Electric Boat. The quality of our submarine fleet is as bad as the Soviet Fleet during the cold war, and nobody seems to care. The things I could tell you if you wanted to hear it. You are SO right Dave. Thanks again for what you do, there are still a few of us around that are honest Americans and not afraid to admit that they don't know something ;). Keep it alive; I will do my best here in The People's Democratic Republic of CT.

[@garythecyclingnerd6219]

If you’re a person who works outside in the cold, I recommend a heated jacket. You can get ones that use tool batteries and it makes cold mornings tolerable. Plus you don’t have to layer as thick.

[@Maximus-bu6eg]

Love my block heater. Start and go. No warm up needed. No idling needed. Hmmm great idea

[@JH-un1vt]

Yes sir! If they only had something like that on diesels...😂

[@genehart261]

I always plug in my old Cummins block heater when it's below 40 degrees f. Truck and I are both happier.

[@oliverroedel1111]

@@JH-un1vt webasto has

[@davidbulich1254]

I warm mine up a little bit more in the winter and change my oil more often in the winter

[@graywolf2694]

My car is gonna blow up, I fix other peoples stuff and don't want to work on mine, I'm over 500 miles

[@elc7795]

You actually used the scientific method to support your claim. I appreciate the effort and information provided. I have a fleet of 7.3 powerstrokes and 5.9 24 valve Cummins. I’ll be changing the startup policy for my company. Thank you!

[@WheelsnWild]

good luck with the 7.3 with cold temps. Before doing that, read about the fuel system with a 7.3, 6.0, or a 6.4 or a Cat 3126. The dirty old Farm tractor motor cummins don't care.

[@davidetchellsetchells4692]

Here's the part of the equation that both of you didn't take into account, the trade off is ring wear. Ring wear occurs rapidly when the engine is cold and the oil hasnt pumped up pressure to everything yet. I think it would be intersting to see how much wear occurs at every cold start maybe in a small displacement water cooled engine under controlled conditions, and verify what that is? I know that there are also small displacement deisel engines that are quick to tear down that also could be used for this experiment. Of course then you would have to factor in displacement diffrences ( because we all know as engineers that bigger bores wear more rapidly) i know both of you are extremely busy with other projects, but it might be worth looking into. ( cylinder/ ring wear / cold start wear)

[@ThaRealBummyDavis]

7:10 this is the best sponsored ad I’ve ever seen 😂😂 my man said my guy health

[@CODA-Improvements]

I don’t think I’ll be idling my LML until it comes down from the high idle anymore! Thanks for the real world data. Changes my perspective!

[@droads9986]

This is terrible advice… pistons are still loose oil isn’t flowing… a cold engine will spin bearings and blow head gaskets..

[@dontfit6380]

@@droads9986I agree there’s reasons they put In thermostats and it’s not for our comfort.

[@kcmatloff5707]

5-10 minutes is plenty of time, they warm up fast once the computer brings it upto 1500rpm, kicks the exhaust brake on and cycles the egr.

[@dontfit6380]

@kcmatloff5707 I can tell you my 17 Duramax is not up to temp in that amount of time when it’s 0 outside let alone -15 with the wind blowing.

[@100pyatt]

​@@droads9986 light load, low rpm has always been the ideal way to warm up an engine especially a diesel that makes very little heat at idle compared to gas.

[@munozinni]

14:14 I really don’t know what you guys are doing with the test but I’m sure you’re doing it in behalf of the truck owners…Saludos!!!👋😃👋 Y’all have a great weekend 👋😃👋

[@jims2165]

Well just got my first low oil pressure following Dave’s advice on my 2017 5.0 Cummings diesel with 96K miles. Getting it towed Monday and hopefully not main bearings.

[@flashcar60]

It's not only temperature which affects piston-ring contact with the cylinder lining; it's manifold pressure as well. When we break in new or overhauled aircraft piston engines, we take off at full power, and run it for a couple of hours at the highest manifold pressure allowed. If not, there will likely be cylinder glazing.

[@thomasroth4695]

Old truckers would pick idle up to about 900-1000 if it was gonna idle. Wet Stack

[@batssorandom]

Won’t allow my card to idle much anymore! And the space heater was actually a good idea.

[@markitoxi]

Great! Could you guys do one on engines designed for low viscosity oil???? Many people swear thin oil it’s enemy for those engines

[@cje26]

This! The 3.0 Duramax community can't wrap their heads around this

[@jimsgaragetoys]

I loved seeing this! I've been telling people for decades this exact same thing, and for the exact same reason! I was curious though to see how the coolant temp didn't rise very much with 10 minutes of driving on the truck. I always see my coolant temp rising faster than the oil temp on my cars. Great job. I wish that I could do my current oil testing with Lake that I just started in as short of a time!

[@lf3566]

I don’t doubt you at all however I have a 2005 Ford Excursion 6.0 Powerstroke Diesel with 343k miles that’s bone stock except for a delete and it’s idled for over 30 minutes every day in the summer before driving it and over an hour every day in the winter before driving it and it’s been a very reliable vehicle that’s never given me problems.

[@Mr.Bearded.Mechanic]

It was a nice test, with video proofs and another cool guy presenting the result. This is the best video so far this year!

[@Dan-vy8he]

Love these details, thanks Dave and Lake

[@DavesAutoCenterCenterville]

Our pleasure!

[@berentjan]

Thanks Dave! Very useful info!

[@user-gr4zt3nv7l]

I have a 2018 Ram 3500, I don't have heat whether I let it idle for an hour or drive it for an hour. By looking at these tests might as well just get a space heater and send it lol 😆

[@friesengarett1376]

In my experience longer idle times have no inherent difference in engine wear. I live in Yellowknife Northwest Territories Canada which is located in the sub arctic. Temps in the winter can get as low as a core temp of -52C (-62F) all the way down to -62C with the windchill (-80F). Now these arent normal temps, but typical winter temps are anywhere between -20C to -50C. I have lived in Yellowknife for 26 years, and over that time I have had several vehicles; not because Ive had engine issues but changing needs/wants, wanting a fun secondary car, etc. Everyone here idles their car in the winters. I personally have a trickle charger, block heater, oil pan heater, and battery blanket on my cars, yet on the coldest of days you still need to idle your vehicles at least 15 minutes. If you were to cold start and drive after a minute your oil pressure would be insane, your power steering hose would explode under the high pressure. I have yet to meet anyone up here who has had catastrophic engine damage due to high idling times. Im not saying its good for your vehicle, but the narrative youre framing it around is much more severe than it actually is.

[@user-zo6xg8bx4l]

That was a GREAT experiment!! THANK YOU!!! 😀

[@DavesAutoCenterCenterville]

Thanks for watching! 👍

[@user-zo6xg8bx4l]

@@DavesAutoCenterCenterville I regularly recommend your channel to others. Thank you again for what you are doing!!

[@brian2359]

I just plug mine in on a timer and I’m set in the morning! Not hard

[@Sd-Dirt]

A few questions: 1. Flashpoint, diesel starts to turn to vapor around 125F. If you were to repeat the test but drive the vehicle after each warm-up, will the results be different? It seems like at least some of this fuel will be recycled through the PCV system. 2. If you always allow the regen to complete like you should, isn't the dpf soot a moot point? 3. Does the exhaust from a cold start actually contain significantly more soot? It seems like there would be minimal difference as the combusted fuel on a cold start has the same or more available oxygen. Only some of the fuel isn't combusting due to poor atomization. 4. Did you test the oil for metallic contamination for each test to determine how bad a little fuel in the oil actually is for the engine? (This may require a longer duration test)

[@8lakk5unshine]

Great video, and Lake Speed the expert to explain it all! Clearly the best thing to do after a cold start is to let the idle settle, then drive the vehicle at under 3k RPM until up to temp. Next I'd like to see a test of what contaminents we would find in Diddy's baby oil.

[@3RCreations]

awesome test Dave, very thorough, I am impressed and a believer. would you consider doing the same test on a gas vehicle with about 100k on it?

[@barrychancey2028]

You stacked the deck by using a diesel. The way the combustion cycle and the way it's fueled is completely different than a gas engine. It has 42% more...more than what? Also after you let it idle no one just shuts their vehicle off. They get into it and drive it which will quickly come up to temp and evaporate any fuel in the oil. Also none of this means anything if you can't link it to measurable wear.

[@gibson5056]

Noob

[@100pyatt]

42% more fuel contamination idling vs low load warmup , he stated that in the video

[@100pyatt]

And diesel doesn't "Vaporize" in the oil at all.

[@martinskamla6789]

Not a great test methodology If you idled it THEN drove it in the first test And only drove it in the second I wonder how much of that fuel would have evaporated on the drive Nobody idles and then turns their truck off

[@jrfish007]

Seems the larger issue is those that don’t drive to a warm up and never evaporate the fuel off. It’s worse with diesel because diesel is harder to evaporate than say gas.

[@DaveBigDawg]

Exactly, this is a terrible comparison, Any fuel and moisture in the oil will boil off once up to the correct temperature in the drive cycle

[@uncleKai_SWW]

@@DaveBigDawgyes but also the dilution to the fuel has been done. Lower viscosity, lower TBN. This is fine if you just change the oil no matter what quality oil to just change it every 3k. However, idling causes more soot.

[@Sixpointtwoliter]

The point is that you let it sit for 10 minutes to warm up everyday over its life. Where the fuel dumped oil is lubricating the engine, and that little by little that 10 minutes of poor lubrication over and over matters. Versus just driving and always avoiding that problem in the first place. He's just showing you what happens as it sits

[@B7mechanics]

If this was the case no truck would have fuel in the oil because it “evaporated off” everytime the truck got up to operating temp

[@greyhairedmountainbiker116]

Came for the oil and stayed for the '68 El Camino. 😂 Results are interesting but not too surprising because my diesel truck heats faster when driving. I'd love to see this experiment done on a gas engine. My dad (50 year mechanic) always taught me to warm the engine (gas) before putting under load (due to ring clearance). The fuel temp discussion is also interesting; Duramax has a cooler on the fuel return, but it gets so hot things start to melt, so probably an extreme case.

[@christopherjarrett6008]

Here’s one for you, test a high idle vs driving it. Mine typically warms faster that way than just driving it. It may have to do with the VGT closing to assist in retaining as much heat as possible.

[@MarkVanTasell]

THE WAY I SEE IT IF ONE CAN AFFORD A 100K PICKUP (KEEP IN THE GARAGE)

[@stefanpuffer]

How much for a new stomach?

[@iddddaduncan]

Not a good test You need to let one truck idle for 10min then drive both for the same length of time, after both engines are well into operating temperature then test oil samples. This test doesn't take into account of impurities that burn off once motors get to operating temps.

[@rondail5675]

That's what I wonder. Will gas evaporate from the oil once the engine is at full operating temperature?

[@andyc935]

I don't think it matters because the fact that the oil was contaminated in the first place means the oil wasn't protecting and lubricating the engine properly therefore it most likely experienced more wear. That's my thought process.

[@iddddaduncan]

@@rondail5675 It has to evaporate or else everyone's oil would be full of gas. He said the one sample had 40% more gas but never said how much gas was in the other sample? saying 40% doesn't mean very much unless we know how much gas was in the other sample, it could be an extremely insignificant amount to begin with.

[@patrickhurley4015]

This is pretty cool taking the time to show it. I’ve known this for years engines just need to get moving yeah if it’s super cold let it warms a few minutes saying 6 mins….. and your fine …. Many years on the road rushing out the door in all kinds of weather always warms up bay the 3rd mile don’t run the air until you hit 3 miles. It’s not rocket science but if idling causes issues obviously don’t do it for longer than 4 mins majority of the time and the space heater is def good idea for 20 mins instead of running the fuel lower not moving. It’s yours so do what you want but don’t ignore logic this guy is very experienced and educated.

[@FireBosspilot]

Common practice to run your engine brake for winter starts on fast idle, loads the engine more so than unloaded fast idle. Warms up much quicker.

[@Brandon-m2q]

Exactly what I was gonna say. Spot on 👍high idle with exaust break on in 10 minutes water temperature is up to 130 on my 06 cummins. Been doing it for years.