Piston Slap??

[TogaPC]

When was the last time you tuned up your engine...plugs, wires, fuel filter, cleaned MAF and Throttle body? Do you SeaFoam? Do you have a Performance Tune?

The rattling at higher RPM's may be a sign that a crank or cam bearing is going out. I would probably take it easy till you have a mechanic tell you otherwise.

FYI - My tahoe did this one morning last month when I parked outside and it was in the 30's. Sounded really bad for about 30 seconds then started idling normally. I also got a MIL for Multiple Random Cylinder Misfire. This has not happened since but I park in a garage. I also have a Black Bear 93 octane tune and I think my fuel pump is starting to go out so all those factors may have contributed to the rough idle.

 

[blueflamed03]

I've never heard of higher octane fuel fixing piston slap. Too bad no gas station here sells higher than 91 otherwise I might try it. Maybe what you had was pinging not piston slap.

I think someone confuses piston slap and detonation. Higher octane gas, will stop detonation, not piston slap.

 

[rich5368]

I think someone confuses piston slap and detonation. Higher octane gas, will stop detonation, not piston slap.

Kinda what I was thinking. I just said pinging instead of detonation lol

 

[blueflamed03]

yep, agree with you 100%

 

[tahoe7689]

I have the exact same problem, and I also have some sort of performance loss, not sure if its related

 

[ugtsmkd]

Hello all i am new to the forums been lurking in the background reading up on various things for my 2001 tahoe. ANYWAY for several years we have used my tahoe as a tow vehicle for my 1970 camaro bracket car. it was recently retired when i acquired a enclosed trailer for the car and the hoe just wasnt cutting it. I had noticed that same noise for quite some time along with a noticeable loss of power and lower mpg. Now this is probably not what caused your problems but it might be somthing to look into. i noticed one of my spark plug wires jiggled pretty freely compared to the rest so i pulled it off and crazy enough the spark plug had started to back out of the head. i then found 1 more than had done the same thing. so i decided to replace my wires and check all the plugs. Since then the noise has completely stopped and the it once again feels like a new car. While it is summer and im not starting it in below freezing weather it was making the noise at any temperature before the engine got to normal running temp.

Just thought id let you all know. It might be something to look for. a very simple fix for a troubling problem although i doubt that is the case for most of you. But maybe with some luck that is the case

 

[greenhornet]

piston slap

I hope its not bad, I have the same thing when I start mine in the cold. It goes away after a few minutes so i dont drive it till that noise is gone. Mine is at 138,???

The usual cause is a worn piston skirt ,not bad but annoying,also the wrist pin (offset slightly) was moved in later versions of the 5.3 to stop cold start noises.

 

[Max]

Mine does it but I can't hear the slap at 6000rpm

 

[HK-DEMON-]

I wouldnt worry i have that issue also, i have to atleast warm it up a couple of minutes before that ticking goes away in a cold morning.

 

[04YUKON]

Just an idea... But i have 120k on mine and last week i herd the loud knocking and again on hard acceleration... Worried i took it in and found that it was one of my cats.. The guts were all fuked up on one side... I still have a slight ticking but no knocking.. I replaced the cats and exhaust....
Possibilty it could be yer problem too..