Originally Posted By: NHHEMI
Originally Posted By: OVERK1LL
Originally Posted By: NHHEMI
It should be noted that for the most part GM solved the piston slap issue by the 2004/2005 model year. At least for the truck V8's. I seem to recall they used a different/longer sleeve to solve it? Maybe a different piston material /deasign as well? Can't recall the exact details.
Some folks still complain about it in newer vehicles but I have my doubts it is the exact same issue as they are a small group vs what it was when this was a very common issue.
FWIW I had a 2005 Silverado with the HO 5.3L( aluminum block 310 HP version not the standard 295 HP cast iron block )and a 2007(NBS ) with the 315 HP cast 5.3L and I had zero piston slap issues. In my time on the Chevy truck sites I did not read about piston slap being an issue for people from 05 on. 99-03/04 seemed to be the main time line for the problem.
They coated the skirts in Teflon like Ford does.
The reason they slap is the loose piston-to-bore clearance. The blocks are bulk-bored and the pistons are bulk-fitted. There is no matching of pistons to bores. So some engines end up with clearances on the loose side and these ones slap. Some don't, and so they don't.
The issue is compounded by the short pistons with very short skirts as well.
I hadn't heard about the teflon. I am pretty sure they used longer sleeves to help stop it by the 05 model year. I am aware of the clearance and short skirt issue. Posted about it earlier.
Old-style piston:
New-style piston:
I think you mean skirts, not sleeves?