What is Piston Slap?

Piston slap is when the skirt of the piston has worn. When cold a light knocking noise can be heard. However when warm, it goes away. the 3.1 and

Would a 4.3 V6 also have this problem or could it be a sticky lifter?

"Cam" wrote

Huh? What engines are you talking about? I can't remember hearing any lifter noise on any engines when started that would be considered "normal". Certainly not any of the late model GM engines. A normal lifter does not "momentarily tick" when the engine first starts up.

Ian

WTF are you smoking? Goddamn that was entirely wrong.........................

Doc

Piston slap does not affect the 4.3's. Just the 3.1, 3.4, 4.8, 5.3 and 6.0 AFAIK.

Doc

check the above thread. Also go to there is a ton of information on both sites.

"Chuck" wrote

I've changed oil on numerous vehicles in the 24+ years that I've been a technician. Can't say that I've heard lifter noise after changing the oil. You are probably thinking of the momentary bearing knock that you can sometimes hear on some vehicles until they achieve oil pressure.

It's not "normal" for lifters to tick momentarily when you start an engine. You might have run across engines that do that, but it's not "normal".

Ian

Hi!

So I did. And thusly I quote:

(Northstar), 4.8, 5.3, 5.7(LS1), 6.0 or 8.1

So now what? I see the 4.3 in there, but I've never heard one do this personally and I tend to believe what I hear in this group.

William The Guesser

I have NEVER heard a 4.3 with the slap, or anyone with a 4.3 complaining os piston slap. This is the first time I've ever seen it mentioned as affecting the 4.3.

Doc

....AND 8.1L

Hi!

Well, neither of the ones I have are doing it, so if anyone's keeping a list... In fact, the 4.3 in my S-10 is vastly quieter and smoother than the motors in the Colorado and Canyon! (Funny, didn't they advertise those as being quieter than the S-10?) I am also pretty sure that my dad's truck would be nice and quiet too without the majorly loud exhaust on it!

In any case, doesn't the 4.3L V6 predate all of the motors known to have problems with piston slap by quite a long time anyways?

William The Guesser

I know they got the newly designed pistons responsible for "the slap" , but haven't heard one knocking yet. Have you?

Doc

Yes it does, and I'm pretty sure up until they shit-canned it it was still getting old school pitsons in it.

Doc

I've got an 8.1L in my 2500HD that sounds like a diesel as does another person in his 2500HD, both are '02s. The other guy's is sucking a qt. of oil in less than 1K miles now on consumption tests. Mine is approaching that, BUT pulled about 3/4 of a qt. through in under 200 miles while towing my fifth-wheel recently!!! I'm going to monitor this closer when I tow it next and then take it back to the dealer. It will be interesting to see if that usage is "normal!" One would have to take a case of oil along on vacation to make it through mountains, etc. 'Spose that's normal though!!! Funny thing, but I've never had to worry about that with any of my other Chevy trucks, all pre 2000.

They just put new intake manifold bolts in mine this past week based on a TSB. Can't see what replacing the bolts is going to do for oil consumption when the pistons knock and rattle like an engine that has 200K miles on it instead of 19K miles, but gotta go through the motions. The TSB claims oil vapor can get past the intake gaskets. Sure seems smarter to me to replace the original gaskets with BETTER gaskets and then the new bolts.

As the noise and oil usage increases, does the compression drop appreciably on the bad cylinders? Have to think it should due to the wear in the cylinder walls.

One can only hope Chevy is made to face the verdict as Ford did.

> > > View this thread:> > > > >

appreciably

Every single source I've heard or read states that there is no performance problem with the "slappers" and that it doesn't affect longevity.

Hi! (again :-) )

Not to beleaguer the thread, but there's always another question...

Shitcanned? Meaning that you can't have a 4.3 at all anymore? I thought they still put them in fullsize vans and 1/4 trucks?

William The Guesser

I thought I had piston slap in my 18,200mile, 2003 Chevrolet 6.0L 2500HD, took it to the dealer and they said that the fix for GM was to change an o-ring in the oil pump. Got a free oil change, they fixed the problem for about 3 weeks and has started to sing again. I have other problems with the truck, i.e. service 4wd error has been fixed 4 times, two fan motors replaced, and I had a rear axle seal replaced. I am trying to get GM to take this truck back, but they are fighting me quite well. Just my problems added to the piston slap issue. any more thoughts? bruce

How about the lemon law in your state? Truck would qualify in most places, it's been in more than 3 times for the same problem (Service

4WD light)....