Now, I got a complete new LS1 under warranty at 35,805 miles.

Had the piston slap, ended up 4 of 8 cylinder walls out of round by .002
from top to bottom.

Now, the new LS1 has same piston slap, as I was told would happen at the 25,000 mile mark.

Yeah, it goes away after warm up, but just pisses me off.

Was curious if anyone using any teflon or any other additive ?

 

that piston slap is pretty common thing for the fbody. on my 2000 i havent noticed it 1 bit. one thing that i have noticed though is that alot of people who have piston slap run synthetic oil then when some who switched to regular oil it doesnt really occur. its just something that i have noticed. i run castrol gtx and i havent had any problems as well as oil consumption running regular oil. hopefully this helps.

 

thanks, shoud have listed, i run only mobil 1 10w30, tried that heavier viscosity of mobil one, same knock... some people swear by redline oil

 

I use Mobil 1 synthetic to. I hear it now and then. I guess I got used to it. Doesnt bother me much anymore.

 

yeah thats another thing. it seems like a now and then kinda thing. there is a site that i saw and cant remember where the person talks bout the piston slap then starts saying its the 0 ring and all that other fun stuff. but i just cant remember the site.

 

A .030 overbore and some Keith Black pistons should fix the problem