Engine Rod Knock Vs. Piston Slap - Take a listen to both!

[@BlindMansRevenge2002]

I always feel so bad for people when I’m at the gas station filling up and they pull up to the pump with their cars making a rod knock. Or they start the thing up after filling up and they have a rod knock. You never know what circumstances Lead people to that type of situation but I’m glad that I have the automotive knowledge and responsibility to take care of my cars. Thanks, dad!

[@ExiledWolf84]

It really is a blessing to know how to maintain/fix your own stuff, isn't it? I have been in those situations where a family member on the opposite end of the country is having car trouble, but due to distance there isn't anything I can do to help.

[@kathygriffin9465]

Me too. Taught how to take care of various engines

[@TonicofSonic]

FINALLY a video that shows them both no b.s no stupid intro no rambling diva just straight up information. I didn't even need this video but I owe you a beer for this.

[@ExiledWolf84]

I appreciate the comment! I tried to keep rambling to a minimum and feel that I did well with keeping it short!

[@BigKandRtv]

I am happy to see you are keeping that old Caddy alive. Future generations will be glad you did. 👍🏻

[@ExiledWolf84]

Thank you my friend! I have owned it for roughly over a decade now, and it has been a surprisingly good car, considering how old she is!

[@manitoba-op4jx]

@@ExiledWolf84 i'm more of an imperial fan but that cadillac a really nice car and i wish you many happy years with it. 😊 they just don't make seats like those anymore!

[@ExiledWolf84]

Thank you! And yeah.. I had a neighbor with a 73 Fuselage imperial. I LOVED that car!

[@jayplayzlol8701]

Watched this high and I already ordered a new engine for my car. I'm a mechanic now with that nice video ❤

[@ExiledWolf84]

Gotta start somewhere, right! 😜

[@Cragified]

Good demonstration of the two. Piston slap is entirely harmless as well. It doesn't cause further wear. It just sounds so loud because of where the skirt of the piston is touching the cylinder as it cocks over at the top. It's like a guitar chamber. The actual impact is incredibly light. It's a nuisance more then anything. When block and pistons are made of widely different materials such as cast iron blocks and aluminum pistons it's unavoidable to some degree as the materials have different expansion rates. And clearances have to be designed for operating temperatures.

[@ExiledWolf84]

Couldn't have said it better myself!

[@gailsmith9835]

Had a 63 buick lesabre once. 401 had piston slap .would go away soon as it would warm up.made a hollow bell like sound.drove it for years. Never did fail.

[@ExiledWolf84]

Sounds like it was a hell of a car. I've never had the opportunity to own a car with a Buick Nailhead V8, but always read that they were wonderful motors because of how much torque the had!

[@FrostyBob99]

I had a 71 Skylark with a 70 455 in it. It had piston slap too. That engine lasted longer than the rest of the car did. I ruthlessly beat on that thing too 😂

[@jerryfarmer5989]

I got a car that I been driving going on 18 years. It has a lifter ticking, no push rods, every since. Finally put in new lifters, don't ride on cam or ever touch it, now you can the piston slap. I'll drive it till it blows up.

[@LostInPhilly89]

I recently bought a 2005 Outback to use as a daily beater and family hauler. When my mechanic gave it a once over he insisted that it had rod knock. 2,400 miles later and the engine is still chugging along. After watching your video, I am convinced that the engine just has some piston slap from 180K miles of wear and tear.

[@ExiledWolf84]

That's cool! Those noises are pretty unsettling at first!

[@hugokatz]

Its your old friend, Rodney Knock...you can call me Rod. Here to remind you, all that glitters, isn't gold.

[@wcurtin1962]

That year of Cadillac with that slapping sound would be a cause of concern in it's day. I remember when they came out with Teflon buttons for piston skirts.

[@ExiledWolf84]

Pretty high end stuff for back in the day , wasn't it?

[@nfullenwider]

Out of a million random YT suggestions (seriously, idk what they're doing), finally, one I like! I don't have either issue, but I know what to listen out for. Great explanation for this novice!

[@ExiledWolf84]

I appreciate the comment! I have a few videos i have put up recently and this one seems to be getting the most attention from the good old Algorithm!

[@angelawerner7696]

Very helpful advice and illustrations on what these two engine sounds mean.

[@ExiledWolf84]

Glad I could help!

[@godfreypoon5148]

Instructions unclear, found woodpecker in oil pan.

[@ExiledWolf84]

Haha! Damn birds! One of those likes to rap on my steel exhaust flue on my house, and it sounds like a damn machine gun at 7am!! Grrr!

[@RichardBillman]

Dawn works wonders on ducks covered in oil, should work for them too

[@YonkoPapa]

I have told so many people this specifically regarding Subarus EJ engines. People get scared and sell them as soon as they hear a little ticking when it’s literally just piston slap. Explaining once the engine warms up to operating temp and has undergone thermal expansion, the noise will go away.

[@ExiledWolf84]

Funny how many people give up on a perfectly good car just because of some sort of small noise that develops!

[@truckladders4104]

Good video, An add to the piston slap is that forged pistons(rare in most modern OEM engine are fitted to a wider tolerance and are noisy on cold start As they heat they expand and the noise goes away Cast piston (common OEM) are a closure tolerance and expand faster from cold While the cast piston isnt terminal and we have all(me included) Have had that trusty 350 chev that would piston slap in the morning for 50k its not the best sound to hear as a mechanic! We have block heaters in all our vehicles(im in Canada) and keeping the coolant at 90ff all night all but eliminates the piston slap! One of about 10 reasons we use block heaters Besides we can tell the environmental zealots that they are electric trucks!

[@Laqota]

Piston slap is just wear, rod knock is a curse (real scientific fact)

[@ExiledWolf84]

Facts! You know I think I washed over the piston slap part too quickly and didn't mention WHY it tends to happen... But yes.. good old wear and tear.

[@bentboybbz]

​@@ExiledWolf84last week I went and installed a new used engine in my customers Yamaha dirt bike, TTR225 I think it was, his son doesn't know how to change gears, so was riding it on the limiter in first gear for who knows how long 😂, I bet that piston was slapping alright, it was flipped sideways in the cylinder bore, both sides had the piston skirt broken off, just mangled, but I'm the day's leading up to the failure, I noticed that the bikes piston slap was getting worse and worse, so I think you are correct saying that it's caused by piston skirt wear, but I think it's also caused by the cylinder bore being worn into an oval shape, also wearing more towards the top of the bore, it was amazing though, the crankshaft side of the connecting rod and bearing and crankshaft bearings themselves were all in great shape with no excessive play, no discoloration from excessive heat, I was amazed, absolutely could bolt on a new cylinder bore, piston and wrist pin, and a few other parts and that engine will absolutely be a good runner....I appreciate your time and effort my brother! I hope you and everyone else is having a great day or night!

[@ExiledWolf84]

​@@bentboybbz That's actually pretty impressive... That engine must have been screaming before it decided to let go! When I actually worked in car repair we would occasionally get the people who had accidentally switched into 4 wheel low, who had no idea what it was, and they would come to the dealer with the engine screaming not knowing why the car wouldn't go above 35 MPH.... I wonder how many car engines have met a similar fate under the same circumstances....

[@drewfleming7065]

Forged pistons will slap brand new...need more clearance cool due to more expansion when hot then cast pistons...can also "Cold seize" in really cold weather because piston expands faster then cylinders.....

[@rolandsolomon7728]

As we used to say in the CB world of trucker talk........Roddenknockers! 😂

[@patk8417]

Another reason for oil starvation is the timing gear disintegrates (it's freaking plastic) and the pieces wind up plugging the oil pickup tube and starving the pump and everything thereafter of oil! I know. I had one of those. I also fixed it, for a little while, and then had to do it again for a little while more. It's a good thing that the oil pan on that 3800 came right straight out from the bottom! Emery cloth, oversized bearing, and almost straight Lucas aided me.

[@ExiledWolf84]

Huh, I thought you were talking about the old Cadillac engines like mine at first, because they have the same issue with the nylon coated timing gears. I wasn't familiar with the 3800s having the same problem!

[@jalsr.2375]

I remember that.

[@bogdan9560]

The best video! Thank you a lot

[@ExiledWolf84]

Glad you enjoyed it!

[@JosephLance-x9q]

Everyone should be shown this great video, I remember trade school ,something like this was shown 🇨🇦👍👍

[@ExiledWolf84]

Thanks for the comment! 🇨🇦🍁👍

[@ellisblake1927]

You ever hear the knock on high performance chevy motors where the rods have extra clearance between them. Great video

[@riblets1968]

I like this! A lot of us who have had cars with piston slap, e.g., me, can have a hard time telling the difference. Until you get a second opinion on it, you're left wondering if your engine is going to die a horrible death. 😟

[@ExiledWolf84]

Made me nervous when I noticed that it started doing it too! I did a lot of diagnosis to pin point it down, including running it with the valve covers off to see if it was a collapsed lifter or something, but I'm not overly concerned with it now

[@professorstokes6596]

Love the T-shirt.

[@ExiledWolf84]

Haha! Thanks! I just happened to be wearing it when I sat down and made this, and it had had a pretty positive reception!

[@gailsmith9835]

Piston slap. Another good reason to let your engine warm up before drive away.

[@WarriorsPhoto]

This is a good point and something I haven't thought about. Thank you. ❤

[@lothianmcadam1]

Excellent video! Next acustoic demonstration, please: Piston Slap vs. Excessive Valve Lash

[@ExiledWolf84]

Thanks for watching! Might have to do that one in the future!

[@TB-lv2rh]

I had a buddy who drove that Caddy in high school. We could fit 7 people in that car. It was great!!!!

[@ExiledWolf84]

Certainly has some wide-ass seats in it! The most I've done in mine is 5, but i would like to cram more in just for fun!

[@Pendragon69608]

bro you explained everything very well thank you.

[@ExiledWolf84]

I appreciate it man!

[@scottzilla6769]

Please make more videos like this about engines and cars this video is very good

[@ExiledWolf84]

You got it brother!

[@MrBlue-ib7oi]

the sounds, visuals and explanation very nice! I subbed.

[@ExiledWolf84]

Hey! Thanks for the comment and the sub! I am little slow with making new stuff, but it's coming!

[@tommymogaka]

👍🏽 *This video is a relief. Thanks for posting.* I have that the 2nd noise in my 1990 W126 300SE Merc. The sound goes away after warming up as you rightly said. I've stopped driving it and I'm looking for Liqui Moly oil 10W40 with MoS2 to solve the issue. I'll update here if I suceed.

[@ExiledWolf84]

Let me know if you have good results!

[@Vegane_Atombombe]

That shirt is great!

[@ExiledWolf84]

Thanks! Haha! Always made me laugh!

[@gailsmith9835]

Had a 62 buick nailhead with piston slap once. Noise completely went away after warm up.had a hollow bell like sound. Old mechanic said that happens when boring tool gets dull after many engines made.said not to worry about it probably done it since new. I drove it many years never got any worse.

[@Dannysoutherner]

Had a torque converter bolt back out and start tapping the back of the block once. Sounded just like a rod knock. I called a tow and while waiting I crawled under - sure as shit, bolt was out some and kind of beat up. I took it out but still took the tow since it is free. Fixed it up the next day, worked fine.

[@ExiledWolf84]

That's always a relief when stuff like that happens and can be fixed easily, kind of like having some sort of driveline clunk that is caused by loose propeller shaft bolts at the flange or something!

[@indridcold8433]

I have been hearing piston slap for about a decade. Once it warms up, it goes away. I have had my vehicle 29 years.

[@ExiledWolf84]

Hats off to you, for hanging onto it that long!

[@TheKlamminator]

Awesome video

[@ExiledWolf84]

Glad you enjoyed it!

[@yardboy3955]

Thanks, good video, learned something I didnt know.

[@ExiledWolf84]

I appreciate the comment!

[@JamesHolbrook-eh5sp]

Our first family car here in the UK had a bad case of rod knock that got worse as you revved it. I told my wife that was the signal to change up. 1979 Morris Marina 1.3. I wished that the original crew of the UK Top Gear would find and drop something very heavy on it. Horrible car.

[@ExiledWolf84]

I have had a few cars like that over the years! And nothing beats the original UK Top Gear! There was an American version of it that they tried for a season or two, and it was atrocious!

[@zacharidumas4405]

A 3800 buick dying ??? Impossible 😂

[@Drmcclung]

Yeah you have to go a loooooooong way without oil first, and the damn things still run as long as the rods are still in it 😆

[@ExiledWolf84]

No joke, huh? That particular car in the video wasn't cared for at all and had a very, VERY rough life, which I'm sure you could tell from the amount of pine needles built up on it.... But there is a part of me that almost wonders how long it would continue to go with that knock being as bad as it is....

[@Drmcclung]

@@ExiledWolf84 from personal experience with the series 2 (same thing as the 3 really) it would surprise you how unnecessarily strong the crank and rods are; Most of the time these will go til the journals lock up before it breaks a rod or piston. These are some of my favorite "$500 car" engines ever.

[@ExiledWolf84]

​@@Drmcclungalmost makes me want to get the car back so I can test it!

[@rpmevo8]

My folks have an 04 LeSabre Custom with almost 200,000 miles and it doesn’t use a drop of oil since we replaced the upper intake plenum, valve cover gaskets, coolant elbows and oil pan gasket. It is HANDS DOWN the quietest and most reliable car we’ve ever owned!!!

[@el_chilubi7458]

I have a 2grfse engine, i hear a knocking sound that comes and goes away, sometime i can drive the car for a week and hear no sound then 1 day you start to hear it, and then shortly after it goes away. It happens when the engine is warm already and especially if i drive beyond 80kph. It happens also when idling. There is no loss of power though

[@selenelacaze9883]

Haaaa. I love those 75 , 76 Cadillac so much !!! I hope I' ll get one , one day ( I already have bunch of classics saved from the trash most of the time, 1 1964 olds dynamic 88 fiesta, 1 1975 Plymouth Fury 4 doors 225ci 3 speed manual; 1 1970 Plymouth Fury Suburban 225ci automatic A727, 2 Chrysler Voyager 2nd gen europe version, then I have a 1966 Opel Rekord Caravan, and a 1978 Peugeot 504 wagon.).

[@ExiledWolf84]

That's quite the collection you've got! And the Cadillac has been a great car in the decade or so I have had it. For being as old as it is, it's a very pleasant car to drive as well .. comfortable, quiet, glides right along. Good heat and A/C. Quite the step up from my first classic car - a 78 Landcruiser FJ40, which will go anywhere, but it beats the hell out of you while en route!

[@selenelacaze9883]

@@ExiledWolf84 Yeaaah I' m pretty satisfied, but I love so much many other cars XD. First I have to get the mback to road condition :) . Ho yeah hehe pretty opposed philosophy vehicles :D , and both really great :) .

[@ali84uk]

I have had the big end bearings replaced in mine and its still making a knocking sound which is similar to the piston slap sound in your video but does not go away even when the engine is warmed up. I have driven it 50+ miles with the sound with no problems. Any idea what it could be ?

[@ExiledWolf84]

What kind of motor?

[@TwinShards]

This remind me of a few months ago. My mom's car sitted for a good month+ because the Timing cover was leaking coolant. After i repaired the cover, putted back everything together and started the car i'm pretty sure the knock i was hearing was rod knock. My believe is one of the valve lifters was stuck compressed, knowing this i decided to keep the engine running up to warming temperature and rev-ed it up a little bit. Sure thing it went away and since then no more knock occured. let's be honest i was a bit worried i would have to OPEN IT AGAIN to extract the valve lifters and replace them.

[@ExiledWolf84]

I had that happen with an old Toyota with a 5MGE inline 6.. after getting it rebuilt, I started it up the first time and it sounded like a bunch of nuts and bolts in a blender. Of course I freaked out and called the rebuilder, and they said to just drive it, and that the lifters would pump up and the noise would go away... Sure enough, I took it for a drive, and the noises all vanished within a few minutes!

[@jounistactics]

Thanks! Very interesting.

[@ExiledWolf84]

You're very welcome! Thanks for coming to my tiny channel and watching!

[@Plumbumas]

Great video dude. ☺️

[@ExiledWolf84]

I appreciate the positive feedback!

[@Casper_V1]

Awsome video man!

[@ExiledWolf84]

Thanks buddy! I appreciate the positive feedback!

[@tahustvedt]

Great video. Didn't expect this presentation quality from such a small channel.

[@ExiledWolf84]

I really appreciate that! I finally decided to get this channel up and running and was kind of afraid that I rambled on this one too much, because I wasn't using a script, but I think it actually turned out pretty well!

[@Pete856]

I bought a Ford Ranger cheap from a large used car dealer in their "end of life vehicles" on-line auction. Description was "engine knock and oil leaks". It's an Australian version with a 5 cylinder 3.2L diesel which are well known for piston slap, and sure enough it has piston slap. However, the slap doesn't disappear as the engine warms, it's probably been slapping for years....don't know if I should be worried, didn't pay much for it so might just keep driving and see what happens. BTW, the engine was a little oily looking but hasn't dripped a single drop on my driveway.

[@ExiledWolf84]

Sounds like a sweet truck! Australia got alot of cool cars that we dream of here in the states.... in fact, there is a business in my city called "Left Hand Utes" that converts Australian cars to left hand drive and makes them legal to drive here.

[@aciddiver1978]

I actually like the piston slap noise.

[@ExiledWolf84]

Kind of sounds cool in a way, doesn't it?

[@aciddiver1978]

​@@ExiledWolf84yes it does👍 definately nothing to do a repair on before it becomes a problem..

[@rpmevo8]

Forged pistons like to make this noise a lot until they warm up. Lol. My 03 Cobra drove me nuts with this noise but after awhile I accepted it as normal. Now I have a tuned Ecoboost twin turbo V6 that has clickity clack noises of its own, so same thing all over again. 😂

[@tylerhubbell6410]

My 98 cobra did the same thing lol it only had 86,000 on it before I sold it.

[@GeneralSulla]

My wife's '06 GMC Sierra developed the second noise. Sounds like a very quiet fart. Could be the exhaust manifold, could be the exhaust pipemanifold connection. Either way, she's sold in Spring.

[@ExiledWolf84]

Seems to be common aith tha GM V8s of the time, although they seem to get by juat fine for the nost part!

[@x2006charger]

My 02 silverado 6.0 does it.

[@UncleBoss-cr1cb]

My '96 Olds 98 has rod knock after blowing a head gasket. Ended up doing a lot of work replacing about 80% of the motor. However, the oil pan looked like somebody emptied an etch-a-sketch in it, and there was about a good quarter inch of slop on the 1 & 3 connecting rods. Bearings were smoked, new bearing obviously didn't help. Washing my hands of the situation after spending my whole summer working on the car just to get nowhere. I don't regret it because this was my first major project and I learned a lot, but it's still a bummer it ended this way.

[@ExiledWolf84]

Funny how projects like that can lead to learning invaluable new skills. I have a similar story with an 87 Toyota Cressida that I bought about 20 years ago with a blown motor, and took it apart completely and had it rebuilt. I owned the car for roughly 5 years, and spent stupid amounts of money on getting nowhere, but the amount of auto mechanic skills I learned with that car have helped me immensely over the years.

[@Drmcclung]

A little cold piston slap out of a 300,000 mile motor never hurt nobody :)

[@ExiledWolf84]

Damn right! One of my cars has 307,000 miles on it, which is kind of nice, because you certainly don't give a rats ass about loading more miles onto it!

[@BryanWiliams]

I have a 98 F150 with the Windsor 4.6 with 256k. And has piston slap. I even heard one with only 30k make the piston slap noise. Everyone told me it's a Windsor thing?. But it goes away once the engine warms up and still runs great.

[@ExiledWolf84]

Seems kike some engines are susceptible to it, so perhaps the Windsor engines are one of them!

[@alanincardona1879]

That first noise is what i call an expensive noise. It will be expensive to repair or replace!

[@ExiledWolf84]

Haha! I like that!

[@wwiimotorpool3967]

My Jeep Cherokee made it over 100k with piston slap, at 263171, it finally broke and punched a hole in # 5 cylinder. Thank you Chrysler for cheapened up on piston skirt walls in 95. I ended up putting in an engine out of a 90 Comanche. Better built engine, thicker skirts.....Hopefully with this one I can make it to a million!

[@ExiledWolf84]

I've seen a few comments on the Jeep 4.0s having that issue .. I'm guessing it's a common problem?

[@wwiimotorpool3967]

@ExiledWolf84 Yes, very common on 4.0 made from 95 on. Piston skirts fall off around 120k due to thinner piston walls. Too reliable the way they were made before. Average life of a 4.0 before changes is about 400k.

[@RyanMcIntyre]

Chrysler has been cheap shit since LOOONG before 95 lol

[@bsd123me]

I have a 99 Cherokee with the 4.0. It has 300,000 on it. Original engine, trance and drive train. The only thing I ever did to the engine was replace the valve cover gasket. I just like to add that I’ve been driving this jeep for over 20 years. It had 40,000 miles on it when I purchased it. My grandson is now driving it. I purchased a 2006 Lexus GX 470. It has 200,000 miles on it and runs like a clock. I purchased it because it’s four-wheel-drive and has a V8.

[@David-yy7lb]

I see you like Sanford and son😁👍🏿

[@ExiledWolf84]

It was a good show, honestly!

[@jeffarcher400]

Thanks. Maybe you can do a video on detonation/ pre-ignition vs valve lifter adjustment noise. Is it ticking or clicking...I don't know.

[@ExiledWolf84]

Not bad suggestions! It's pretty easy to hear pre-detonation here in the high country... You just have to put in the crappy 85 octane gas that they sell here, and then give the car a lot of gas heading up into the mountains.... I might have to try getting it on camera!

[@StraightWhitearrow]

Wrist pins get accused for knocks as well

[@Yan1nc]

My old 97 Chevy Lumina had 860 000 miles on the original engine and the piston slap was awful, but still ran until I had to send it to the Junkyard since the chassis was completely rotted

[@ExiledWolf84]

That's unfortunate. The damn rust monster never sleeps..

[@slavikrybka]

Piston slap is a common problem for Honda L-series engines with i-DSI that can be found in JDM Honda Fit 2001-2008 or European Honda Jazz 2002-2008. Unfortunately the sound doesn't go off after warming up the engine and at certain conditions at some RPM comes into resonance and make you question your life choices, but, I bought this car with 195k km on the clock (122k miles) and so far, after 4 years and additional 132k km (83k miles), it runs the same. And let it be this way.

[@ExiledWolf84]

I wonder why that is? Machining tolerances at the factory or something?

[@jacobrzeszewski6527]

Can you do a video showing ping. I've heard people describe the sound but I haven't seen a video demonstrating it.

[@ExiledWolf84]

You know the rest of my family just puts the old' garbage 85 octane in their cars, and some of them ping something awful when they are accelerating up the steep hills in the mountains... It is a very faint sound, and might be difficult to catch on camera, but I could certainly try sometime to get it on film!

[@operationoverloard]

Teach the masses the differences between piston slap and wrist pin noise.

[@FFM0594]

Could you do a side by side comparison of the piston slap and then the same motor when it has warmed up? Thanks!

[@ExiledWolf84]

Not a bad idea! I think I will! Thanks!

[@arthurgay5746]

If you ever heard a diesel engine idling, that's piston slap . Piston slap with run indefinitely depending on the situation. The rod knock sounds like a man in the basement hitting steel pipes with a hammer. That noise will suddenly stop in the very near future and you will have to walk home...

[@ExiledWolf84]

Oh yeah, the first time I heard that Buick in the video making the noise, that was the first thing that came to mind. Someone smacking the shit out of something with a hammer!

[@no-damn-alias]

I have a car with piston slap and had it for years. No oil consumption, no issue. Standard issue on VW 1.4 16v

[@basherbodies7285]

Good vid buddy!

[@ExiledWolf84]

I appreciate it man!

[@toodjackson4438]

We just pulled a 75 Cadillac like that out of a barn yesterday that's been sitting there for 30+ years

[@ExiledWolf84]

Very nice! Do you know what year it is? The one thing thats nice with the Cadillacs of fhe era is that quite a few of the parts are still widely available, as oppoosed to the 76' lincoln i once had, which was like searching for hens teeth whenever it needed something

[@toodjackson4438]

​@@ExiledWolf841975

[@toodjackson4438]

​@@ExiledWolf841975

[@toodjackson4438]

​@@ExiledWolf841975

[@thomasward4505]

What is the difference between piston slap and a slightly worn wrist pin. Both of them will go away when the engine warms up

[@ExiledWolf84]

From what I understand piston slap is cause from either wear on the piston rings, or from wear in the bore, almost like it's becoming slightly oval. I didn't cover it in the video because I simply forgot to talk about it, but as the piston expands with heat, it fills the bore a little better and the sound goes away. I don't personally have experience with a worn wrist pin yet so I can't comment on it myself, but I imagine the noise would be similar depending on the wear!

[@justsumguy2u]

I had a Corolla with piston slap. When the engine was cold, it was loud....sounded exactly like a rod knock. But once the engine warmed up, it was barely audible

[@ExiledWolf84]

I have a soft spot for Corollas. I learned to drive on a 96 with a manual transmission, and have owned several others over the years.

[@tylerhubbell6410]

I have piston slap on my 2000 gmc sierra.Apparently its a known common thing with the 4.8,5.3,and 6.0 truck engines.Like in the video it goes away after the first few minutes of the engine starting and warming up.Lucas oil stabilizer doesn't help make it go away.

[@ExiledWolf84]

Very common on those as i have been told! I had an Escalade sith the 6.0 that never developed it, but it had other issues from lack of maintenance from the previous owner

[@castirondude]

A good test is to put super thick oil in the engine. If that fixes it then it's rod knock. If that doesn't fix it, it's piston slap. I have a crown vic that sounds like the Cadillac but thick oil won't quiet it. It was retired from the police dept at 80k miles because of the knock. I put another 80k on it and it still sounds the same.

[@ExiledWolf84]

I've almost been curious to put gear oil into the Buick just to see if it actually makes a difference.... The poor car is WAY beyond saving, so why not use it as an experiment?

[@castirondude]

@@ExiledWolf84 Yea. How easy is it to get the oil pan off? Maybe you can install an undersize bearing shell in it to get it close and then use the thick oil. I just searched "gm 231 undersize bearing shell" and they do have em .010 over. Plastigage it to see how close you are.

[@ExiledWolf84]

I have heard some people on here comment that the 3800s have an easy to remove oil pan... But as of now the car is no longer in my possession, but I guess I'll see which way it goes for it in the future!

[@louisrichards3702]

just how much clearance does it take to have rod knock?? anyone know? thanks.

[@ExiledWolf84]

I wish I knew specifics!

[@jonathanlyman5705]

I heard that first noise this morning in my 99 grand marquis or my right passenger.... something hit my valve cover it sounds like something came loose... my dad something about my tappet bolt might be loose

[@teebag2764]

I want that shirt where did you get it

[@ExiledWolf84]

Haha! Honestly my mom bought it for one of my birthdays about 20 years ago, but if you do a Google search for the words, there are still quite a few other places that sell shirts with the same text on them!

[@cdoublejj]

my kawasaki quad has a sound inbetween both sounds and it doesn't fully go away, giving some revs makes it seems a little less, it's been this way for a good while now but, i hardly put any hours on it each year. it was seized when i got, wristed pin was rainbow colored and took a 5 pound hammer to remove, chinese piston kit whent in and bore job form the cycle shop, no bottom end service.

[@ExiledWolf84]

That's interesting, and I'll say that it's cool that you got it running again! Which part of it was seized? The wrist pin?

[@bentboybbz]

Is it a bayou ? I had one that had what I assume was either a wrist pin issue, piston slap, maybe a clearance issue and the piston was hitting the head? Maybe a combination of those? But it never got worse, even when it was 100F and we were passing that poor thing around to 4-10 of my friends all day into the night, it was driven into the pond multiple times and hydro locked, twice it was buried so badly next to the pond I had to leave it overnight, so bad that I left the key, figured if someone worked hard enough to get it out they can have it, 😂, but I beat it into overheating over and over trying to free it over two full days, would let it cool off until the light went out and go again lol, basically what I'm saying is that I was told it was a wrist pin noise and it never got worse, never caused me a single issue, still ran pretty good considering the abuse I put it through when I sold it, I know that the new owner gave it to his son and he beat it for two years before they sold it on, I always made sure to change the oil and filter frequently, made sure it never was low on oil, always used high quality oil, and I always made sure I warmed it up, especially on cold days, even on Hot days I ran it for 4-6 minutes before riding, I do remember that the noise was considerably louder when cold so I feared that revving or riding it before it was warm enough to quiet down would be what hurt the poor thing 😂, I hope at least some of that makes sense, and that maybe it will help you not worry as much and enjoy riding your quad, or is helpful to you or anyone else in some way, if you have any questions don't hesitate to ask, heck I don't mind if you just want to chat, no one looks out for each other anymore and it's making everything so much more difficult than it has to be, I appreciate your time and effort! I hope everyone is having a great day or night!

[@carleynorthcoast1915]

I always thought it could knock at the wrist pin, crank bearing or journal. Half the time it's just a stuck lifter and it goes away.

[@wstxiseeyou]

Had piston slap in a boosted integra. Made 463 on dyno. Beat on it every day for years before i traded it for a BMW. Reving you could hear the slapping. Went away during high rpm 😂

[@ExiledWolf84]

I'll bet that thing was a blast. Honda builds a hell of a motor, that's for sure!

[@benruether8294]

Very common in performance builds with forged pistons. It's better to be a tad loose with boost than too tight

[@Dingo-the-dingus]

You know what they say.....keep going until it dont knock no more

[@phillyups3023]

Damn that the first time I heard that with a 3800 series 3

[@ExiledWolf84]

Right? The poor girl took a beating the last few years of it's life!

[@sherdawg]

Subaru: I will have both

[@dxrflyboy]

Both noises actually come from the piston. The "rod knock" is caused by the piston hitting the cylinder head during the exhaust stroke. If you disable the spark to the affected cylinder you will hear the piston hit the head on both crankshaft revolutions instead of just the exhaust stroke. As far as blowing it up, I once "blew up" a Buick V6 that I was replacing. The first thing I did was hold the pedal to the floor for a few seconds. I had to let up because it filled the shop with smoke. Then I drained the oil out of it. It knocked worse and worse but kept running. Finally I drained the coolant out of it and it eventually stopped running, but did not grenade in spectacular fashion, to my disappointment.

[@ExiledWolf84]

I might have to try that before the car goes to the auto graveyard... Might be interesting....

[@Oleg-fp9hn]

I wouldn't 100% agree. Some engines have significant piston-engine block deck clearance. For example bmw m54b30 it is 3mm - more than rod bearing thickness. But for some engines yes - rod bearing spun cause engine head damage.

[@j.bru_36]

My old 5.3 Chevy has had piston slap for 20 years 😂 she’s at 270,000 miles and runs like a top once it warms up haha

[@ExiledWolf84]

The good old 5.3 is a hell of a motor.

[@timr31908]

What about wrist pin knock.. I think it's a double knock noise.. metallic noise

[@ExiledWolf84]

It's hard for me to comment on that one since I haven't personally experienced it yet, but from what I've been told it's a little less consistent and sounds *sloppier* than rod bearing knock, simply because you have the element of the piston rattling around as well! That and the fact that it's a little more rare because wrist pins are seemingly made out of the hardest material known to humankind! 😜

[@billwill7383]

I like your shirt.

[@ExiledWolf84]

Haha! Thanks! I got it as a gift like... 20 years ago and it still makes people chuckle!

[@Campbase1]

What is it if that piston slap noise starts when its warmed up. Its not loud but noticeable. No sound when cold.

[@ExiledWolf84]

It's hard for me to tell you exactly, because it can be a number of other issues, everything from valve lash to clearance issues with something else... What kind of engine, if I may ask?

[@Campbase1]

Its a 1975 Mopar 440. I have trick flow heads on it and harland sharp rockers. It seems to be a solid motor. I have 5000 miles on it since the rebuild. It just seems strange that it is quiet during warm-up but a but noisy after warm-up.

[@adamrobledo684]

Yessssss I have piston slap 🙏🏼

[@jagesosot]

Piston slap can be normal on some engines when they are cold. In the toyota IQ instruction book it says that piston slap is normal when the engine is cold. However if it never stops it might be a good idea to get it to a mechanic. I have had a car with same engine (aygo) it have always have some piston slap and never failed (8 years).

[@ExiledWolf84]

Interesting! Do you know if that's the 3 cylinder, or 4 cylinder model? We BRIEFLY got the Toyota IQ across the pond here, which was sold as the Scion IQ (Toyotas defunct youth brand) with the 4 cylinder engine, but they didn't move many examples of it so it is somewhat rare, and we never got the Aygo...

[@saab900turbo9]

​@@ExiledWolf84both i have is 3 cylinder ones 1 litre. But there is 1.33 litre 4 cylinder ones too. I do not know if they got piston slap or not.

[@ExiledWolf84]

Ah! I gotcha. I'm thinking that the GR Corolla got we finally got over here has that same 3 cylinder engine, or a variant of it... But it is also turbocharged to hell.. I'm curious to see if they are in the same engine family...

[@MrAppleBrony]

My old Volvo sound like piston slap. But the sound never gose away except when I cold start it in winter then it's silent. Quiets down a little bit after a long drive. For the record it's a well worn engine with probably 450 000km

[@ExiledWolf84]

Good old Volvos run for freaking ever, don't they?

[@riverrail]

With piston slap, I would use combustion cleaner to rule out carbon build up on the piston. Like you said, it will last unless you overheat the engine badly.

[@ExiledWolf84]

Might have to be something I try at some point! I imagine a lot of old big block engines like mine have a lot of carbon buildup, just from the fact that they don't spend a lot of time at very high RPMs from how much torque they have.

[@stevemino142]

Piston slap was common on GM 3100 and 3400 60 degree V6 but has nothing to do with reliability I had 469,000 kilometers on a 98 Buick century with the 3.1 ticked like a clock but always started when I wanted it to.

[@ExiledWolf84]

Buick has always made a hell of a vehicle, haven't they? The particular one in the video was HEAVILY abused and was basically abandoned in the woods for several years, and was run once or twice with no oil... Hence the rod knock... Too bad, because it was a nice car at one point!

[@stevemino142]

@@ExiledWolf84 proper maintenance prevents poor performance...good video

[@ThomasThornton-zh7cl]

with rod knock there is also a problem with the rod journal, it tends to get egg shaped instead of round. that is why you can't just put a new bearing in and go on.

[@ExiledWolf84]

Which really sucks, because I'll bet a lot of them could be fixed relatively easily by dropping the pan and just sliding new bearings in, but unfortunately, like you said, it's never that easy

[@pinkflydnt]

My '99 Silverado Z71 5.3 with close to 300,000 miles has piston slap for about a minute upon first start up of the week then it goes away and it's very quiet (it only gets driven to the dump once a week).

[@ExiledWolf84]

Seems to be a common issue in that generation of GM V8's, and all of them don't care and just keep going too!

[@micahwatz1148]

My car is just making an ultra low pitch thud. You can barley hear it. But you can definitely feel the vibration. Any clue what that is

[@ExiledWolf84]

Could be numerous issues, anything from bad engine mounts to something just being loose somewhere. How would you describe it? Is it rhythmic with the engine speed?

[@micahwatz1148]

@ doesnt seem to be rhythmic. Seems random. Its a 2019 challenger 392 with 26,000 mi

[@ExiledWolf84]

Huh, I used to own that exact same car! Same year and everything! Is it when you are driving? Changing gears? Going over bumps?

[@micahwatz1148]

@ i only feel it at idle. Car is still driving fine

[@ExiledWolf84]

Almost sound like it might be a lose engine mount or something. Those car are under a lot of stress depending on how they are driven, something could have loosened up. Are you still under warranty? ​@@micahwatz1148

[@vinisuichi1243]

What we learned with this: Always be sure your motor have oil!

[@ExiledWolf84]

Oh for sure, huh? It bothers ne how often people just dont five a rats ass on oil and how important it is. I did an oil change for someone once that went almost 25,000 miles since the last time they changed it.. like... Come on... Really?

[@keysautorepair6038]

The 3.3 gm and the 3.8 can be the crankshaft balancer broken sounds exactly the same.

[@ExiledWolf84]

Is that a common problem on those puppies?

[@keysautorepair6038]

@ Yes and it sounds exactly like a rod knock I mean exactly the rubber separation on the crankshaft pulley.

[@davidswanson5436]

Jeep 4.0 piston slap. Legendary

[@ExiledWolf84]

Legendary slap for a legendary motor! ..... Or so I've been told!

[@ludedude5228]

You forgot the timing chain slap when the chain is so worn it literally is slapping against the guides or even the block . That sound never goes away $

[@ExiledWolf84]

The Toyota 22RE is the first engine that comes to mind with you saying that. The timing chain will literally wear a hole in the chain cover if you let it go for too long!

[@wadewilson6628]

My 5.4L 2V Ford came with piston slap from the factory. 😂

[@ExiledWolf84]

I know the feeling! Haha!

[@DM-wp9vq]

"That sound completely goes away" looks down because he lied to himself. Drop a junkyard LT or LS or Vortec into that great looking Caddy! A standard SBC 350 would be great too!

[@ExiledWolf84]

How about some bull horns, flame paint, and some 25" spinners to go along with it? 😜

[@DM-wp9vq]

@ExiledWolf84 haha, nahhh. Looks great as is. I've been there too. Telling friends "oh that's fine, I just ordered the parts. Gonna put them in when I get them" 3 years later.... friends rediscovering the sound

[@ExiledWolf84]

​@@DM-wp9vqTell me about it! I have STACKS of parts laying around that I need to install, including a bunch for this one, like a new timing chain, oil pickup tube, u-joints, lifters, VIR eliminator and too many other things to count. The interior is torn to bits right now because it needs a new heater core and is getting a retro radio... I just couldn't drive around with only an 8-track player anymore

[@lilyanimate7266]

i rebuilt engines for 20 years and not even 1 time did i see an engine that needed to be rebuilt that was just worn out from running to long someting else always kills them

[@Impactjunky]

The whole "classic cars were only designed to go 100K miles/a couple years" thing is such a BS statement. Classic American cars survived in mass for a reason. My daily driver for the last 15 years has been the same 68 Plymouth and also I've got a 72 Cadillac, 73 Mustang, 67 Cougar, 75 Valiant, 68 Dodge Coronet and an 84 Trans Am that are all still going strong on their original engines and drivetrains and they are all such common cars that I was able to get them cheaply in this day and age. That's not just some fluke. Especially considering there are almost zero classic foreign cars out there running on their original build.

[@ExiledWolf84]

Hmmm, these facts and opinions seem to look pretty similar, don't they? 😜

[@DericCribbs]

rod knock goes away while under load and is loudest while maintaining cruising speed. The first one sounded like a piston pin knocking between the rod and the Piston. never got to hear it under load. why not disassemble it and check the rods

[@ExiledWolf84]

I've considered trying to get the car and actually do a teardown on it, but i'll just say it will probably be some time before the owner decides to actually throw in the towel and let it go, as odd as that sounds!