All About the L5P Duramax Engine! | 4 Common Problems

[@R3lyc]

DEF tank heater meltdown is a very common problem. My 2021 has had a new tank every winter since I got it. They replaced the whole tank each time. The last time it happened we just barely limped it to the dealership. After they fixed it I deleted. No more emission system problems.

[@8020Media]

C - This is true! Thanks for sharing your experience. We are big proponents of deleting emissions systems.. But we can't recommend it, legally.

[@R3lyc]

@@8020Media yeah I hear you, I know things are much stricter in the USA. In Alberta we can delete them, but to be street legal the truck needs a muffler to keep the db at stock level. Some cities are strict with their noise bylaws.

[@8020Media]

C - Yep, exactly!

[@marcelo403polo2]

@@R3lyc Too bad this doesn't apply to stupid motorcycles reving over 10K middle of the night. My LML is straight pipe and never had any problems with noise in cow town

[@R3lyc]

@@marcelo403polo2 it technically does, but it isn’t enforced often. Edmonton was on a big noise kick a few years back, and even tried a noise photo radar system at one point.

[@samdeyton5449]

My 2017 L5P has been fairly good thus far. Only issues have been injector codes, which have all been fixed by replacing the pigtails, not the injectors themselves. It is annoying, but honestly not a big deal. ~ $80 part and an hour or so of work. It’s happened to 2 injectors, #4 and #5, she has 140K miles. Other than that, drives and tows like a dream, happy with her.

[@8020Media]

S - Thanks for taking the time to share your experience! This will certainly help future viewers.

[@m1lkman1974]

Great video thanks. Subscribed!

[@8020Media]

M - Thanks for the feedback and support!

[@bentleyfatheree1616]

160,000 on my 2018 L5P no major problems at all. I've replaced the radio , head lights , tail lights , breaks , batteries , coolant reservoir . That's all

[@8020Media]

B - Sounds like you take great care of it. Thanks for sharing your experience!

[@carlossicilia2658]

Im in the market to buy one any word of advice on making a purchase on 2018 3500hd chevy silverado diesel, its my first diesel haha just curious if should get gas or diesel

[@8020Media]

C - There's a lot more factors that go into this.. Hard for us to really give advice without any background. Is it in your budget? Do you tow a lot? How many miles? We prefer a diesel over gas, but that suits our life better.

[@anthonywiley6649]

Im at 140k miles lp5 , ive replace the nunber 4 injector , radio glitches other then that good truck

[@8020Media]

A - Thanks for taking the time to share your experience!

[@jerryolivas4500]

Def heater is easy to work on till you can’t get your hands on the parts needed. Def lines are back ordered till next month all over. Lucky mine just went out and it seems like I’ll be walking to work for a month

[@8020Media]

Jerry - So sorry to hear this.. thanks for sharing this info. It’ll certainly be helpful to others down the road.

[@jimm2442]

Good information and accurate until you mentioned the Allison 1000 as a 10 speed when in fact it is a 6 speed. The GM Built "Allison Certified" 10L1000 started in use on the 2020's is a 10 speed. Which one were you speaking about?

[@8020Media]

Jim - you're correct, thanks for pointing this out! I misspoke and was thinking about the new 10L1000's.

[@keeganallen393]

@@8020Mediaso what can the previous transmission hold 2017-2019.5?

[@ClayHoffman-c2g]

Glow plug #7 happened to me at 37k. Easy fix though. Started getting DEF and Sensor errors… so I have her a weight reduction at 38k 😜

[@8020Media]

C - Thanks for sharing your experience!

[@martyhatchard9949]

Wow. Awesome info. Input. Thks

[@8020Media]

Marty - Thanks for the feedback! We hope it helps.

[@aco2518]

My brother just bought a brand new 2023 duramax 6.6L, and admittedly I know very little about these engines. Are they relatively easy to work on? I was frightened by the immensity of junk covering the engine when I opened the hood. At least its good to hear that they are reliable.

[@8020Media]

Really depends what work you're trying to do on it - definitely not as easy to work on as the older diesels that have less emissions and electronic systems. Definitely a lot of stuff in there that limits accessibility so really depends on the job but getting to certain parts of the engine can require removing a lot of crap to get access.

[@cyumadbrosummit3534]

Just wake up from a coma? Only drive ancient trucks? Vehicle engines have had junk covering the engines for the last 15-20 years.

[@mikebrown9899]

You didn't mention the boost tube problem. I'VE blown 5!

[@8020Media]

Mike - Thanks for sharing this experience. This will certainly help future viewers.

[@grindelandd]

Turn the burp down dumbass!!!!!!!!fgs!

[@PCGonline]

sold my 15.5 LML for a 17 ford 6.2 gasser for business reasons but kinda wanna buy a 2016-2020 L5P as a personal truck since i miss my denali. thanks for the info man

[@8020Media]

PCG - Thanks for the feedback! Can't go wrong with either - LML or L5P. Both stout.

[@gallardo360]

what years are the l5p in ?

[@8020Media]

G - The L5P are 2017-2023.

[@jponyboyace]

How about the crankshaft pins sheering off…..common as know!!!

[@8020Media]

J - Thanks for the insight.

[@454budman]

No its not. You got that from daves videos and its is very rare. Usually happens to people that remove the balancer and do not tighten back to spec. Also usually from yahoos tuning the balls out of it. Any stock motor past 100 hp over stock is going to be very unreliable

[@8020Media]

M - Thanks for taking the time to share this insight!

[@wannabeutuber1]

Not on the l5p

[@neil9503]

I installed a S&B redirect map sensor and took it off 2 weeks latter because i was loosing 4 miles per gallon on hwy..

[@8020Media]

N - Oh wow.. Sorry to hear that. Thanks for sharing!

[@austinharris7037]

Surprised no glowplug mentions guess its a wear item thou. But have replaced 4 in less than 60k moles

[@8020Media]

A - Thanks for taking the time to share your experience!

[@austinharris7037]

I'm ready to delete thou. Just want to now the best safest route

[@austinharris7037]

I'm not after much. I just don't want all that gunk on top my valve train

[@8020Media]

A - It's the way to go!

[@kcthomas786]

Where can u get gold plated connectors?

[@8020Media]

K - For what?

[@nospark333]

@@8020Media I assume he is talking about the injector connectors. LBZ used gold plated pins.

[@grindelandd]

Btw... early l5p owners.... I recommend upgrading to the banks engine oil cooler upgrade kit before you "tinker" with old gran dad! You'll thank me later.

[@8020Media]

Grinde - Great insight here and we totally agree!

[@96318dakotaify]

97k on my 19 and it’s had injectors replaced under warranty sweet, ball joints tie rods all shocks all brakes and one nox sensor, why the hell did they put the def fill under the hood and who ever did should be smacked.

[@8020Media]

9 - Thanks for taking the time to share your experience!

[@JamesWatsonGotMold]

How about the DPF system? My truck is 255% clogged after 54k and over 40k of those km were pulling trailers. Been at the dealer for 8 weeks and no parts available anywhere. They tell me could be 6 - 8 months! 2024 truck sitting inoperable. I can only assume that lots of people have the same issue as parts are not available

[@8020Media]

J - Sorry to hear this.. However, thanks for taking the time to share your experience. I'm sure this will be helpful for many future viewers!

[@nathanmedema5458]

negative. Dont let it idle for long periods. Dont do start and stop driving (i.e. trips to the store and back to home, limit these short trips as much as you can in between your long drives). Also run fuel treatment, your fuel will burn cleaner and create less soot in your DPF. Take it on long drives often... any drive times under 15 minutes are a big no no with these as I have learned. Lastly, dont be afraid to stomp the gas pedal down and run it thru all the gears a time or two during a re-gen, this will help blow the DPF out IMO. Helps also to drive it like you stole it every now and then anyway, cleans the injectors and the regurgitating fart parts as well! 2024 HD 3500 L5P with 70,000 miles to date. I travel 26 miles (one way) to work every day (half the drive highway, half the drive 55mph back roads) and I also take a 500 mile round trip (basically all highway) with it once a week. I do do some in town driving on the weekends with the family, and will purposely keep it on and idling when going from store to store assuming we wont be in the store longer than 5 or 10 minutes.

[@nathanmedema5458]

and the 500 mile trip every week is towing 9000 pounds regularly in an enclosed 9.5 high x 8.5 wide x 24 long trailer.

[@8020Media]

N - Thanks for taking the time to share all these insights. It will certainly be helpful for future viewers!

[@grindelandd]

I have a 2017 dirtymax and it's like a old 6.5l turb. Very simple to wrench on just kinda tight quarters. Lol

[@8020Media]

Grinde - Thanks for sharing your experience!

[@D.Rosebrock]

I've got 2 6.5s still running in my fleet I actually thought about selling to buy a newer truck 😂 I got a 1993 and a 1999 with over 400k on each of them on miles and original transmission and 4x4 as well. I change the oil every 5 k miles the fuel filter every fall before it gets cold and I change the 4x4 and transmission fluid as well once every other year. And the differential fluid as well at that time. Every 5 years I trash the brake fluid because brake fluid does absorb moisture in the air. I also change the antifreeze as well at that time. Knock on wood I still have the original water pumps on both engines in each truck as well. I've never had any trouble other than those dumb silly PMD boxs for the electric injection pump for the newer 1999 isn't mechanical injection. I do tree service work so all in all I'm only fully loaded one way on weight I move 8-13k lbs. Loads daily with both of these trucks in south central Texas. Them old rear drum brakes feel so outdated 😂

[@kpenn2259]

You haven't mentioned the shitty gas mileage. Avery other diesel I've ever had could get 18 all day long hw or pulling. My lifetime is 14.1 mpg in my 18'

[@8020Media]

K - Thanks for sharing your experience and insight.

[@lifeoutdoorseveryday1682]

About the same as mine. I expected better.

[@8020Media]

L - Thanks for sharing your experience.

[@454budman]

Yeah Ive had Ford and Gm, Ford wins by about 2 mpg. I think its the after treatment and the fact that GM piston stroke is shorter so it has to work a little harder to make tq.

[@star4161]

Mine also is 14 mpg lifetime 43,000 miles so far , and park sensor went out and they’re back ordered

[@bluedotoutdoors2423]

Does this truck have cp4? I have a buddy who swears they have the cp4 but everything I’ve read says they switched over.

[@8020Media]

Blue - The L5P ditched the CP4 after the LML.

[@mikethetoolman8776]

l5p is not a bosch system nippondenso, no cp4

[@mathewmcgregor1043]

Just getting the fuel injector connector issue after 4 years of owning. Round two of it now

[@8020Media]

M - Thanks for sharing your experience!

[@JL-ip3sf]

The key word here is maintenance! If you do your maintenance on your vehicles so promise they’ll last. Don’t run them hard unless you really need to.

[@8020Media]

J - 100%! Couldn’t agree more.

[@johnmedina8323]

I’m coming from a 19 Denali that I got rid of because of transmission and lifter failures , which I know a common issues when buying these GM 1500 trucks but I’m wondering do I deal with all of that on the 2500 model as well??

[@8020Media]

John - Yes they have been reported to see lifter failures.

[@johndono6959]

Should have no trans issues.

[@mikethetoolman8776]

2500 doesn;t use the afm-dfm so different lifters

[@gigachad4211]

Im gonna swap a lp5 duramax into my 06 chevy vortec max 6.0 soon

[@8020Media]

Haha share it with us once you do! Sounds like a beast of a swap.

[@WhiteoutSnowy]

Oh yea , other thing will 2025 duramax still be L5P ?

[@8020Media]

J - As of now, yes.

[@WhiteoutSnowy]

It’s not too bad but I think that ford 6.7 HO is better.

[@8020Media]

J - We think they're both great engines!

[@taylorh3930]

Delete it 5" straight pipe exhaust 👊

[@8020Media]

T - If it's legal, for sure!

[@juanmartinezinc59]

Oil leaks like a mofo on 2024s

[@8020Media]

G - That's interesting. Not something we've heard of yet.

[@colestaples2010]

Mine is a piece of crap

[@8020Media]

C - So sorry to hear about this. What's going on with it or what problems have you experienced?

[@colestaples2010]

@@8020Mediaeverything you mentioned plus some. It’s currently consuming a ton of oil

[@8020Media]

C - Thanks for taking the time to share your experience.

[@colestaples2010]

@@8020Media looks like I have a main seal leaking so it’s headed in for warranty work this morning

[@8020Media]

C - At least you found the cause! Keep us updated.

[@grindelandd]

Loving my l5p!

[@8020Media]

Grinde - Thanks for sharing your experience!

[@MrGetloose2000]

They have issues. Trans and engine failures.

[@8020Media]

M - Indeed they do.

[@wannabeutuber1]

Lol very few

[@newlion7013]

So buy a cummins?

[@8020Media]

Lion - Just because we say the L5P had a few problems, doesn’t mean it is unreliable by any means. We’ve seen plenty of reliable chevy’s.

[@johnmedina8323]

Would u recommend getting 2019 l5p ? 20k miles

[@8020Media]

John - We're big fans of L5P's, but we can't and won't recommend any vehicle to anybody. Just because we don't know what you are looking for out of a vehicle.

[@TTGTO288]

Cummins is probably, admittedly a better diesel engine, but there are a few problems with it, 1. It's not a V8, 2. The trucks they come in are junk, 3. Dodge puts garbage transmissions behind them. The L5P is still a good bet even with its minor issues.

[@8020Media]

We have many videos for the Cummins engine as well.

[@TTGTO288]

I am looking to put an L5P into a '63 Impala. This is probably the best that Duramax has put out (so far) and i am looking to completely emissions delete this thing being that its going into a 1963 car. V8 Big Block power that should yeild about 25 mpgs or better in a 3800lb car. I'll have 2 tunes, one for smoke and power and one for fuel mileage. Its going to get driven all over the east coast. No trailer queen here.

[@8020Media]

Sounds like a sick rig you're building! Keep us updated on this.

[@monsaka7827]

Get rid of the smoke and you'll have more power.

[@TTGTO288]

@@monsaka7827 Yes, I know, but not as cool ...

[@monsaka7827]

@@TTGTO288 Nothing cool about black smoke. When you see black smoke you know there's an immature amateur at work.

[@TTGTO288]

@monsaka7827 I will agree and I know it's just wasted fuel and power if its smoking out of the exhaust, but, black smoke billowing out of pipes on either side of the car on the street is just cool. The system I want to run will allow for plenty of tunes, so I will write more than one and will be able to switch between them on the fly, depending on the situation.