LS2 Question

[Jason8691]

I have an 05 GTO with the LS2 and was wondering if there have been any reports with the high copper or piston slap. I have done searches but havent found anything. SO the ultimate question would be what kind of oil would be best for this engine? Its on a diet of 4 qts GC and 2 qts Castrol 5W40 right now.

 

[J. A. Rizzo]

What does GM recommend for it?

 

[Mitch Alsup]

All LS[1267] engines have some amount of piston slap, which is generally mild and goes away in a couple of minutes.

GM recommends 5w30 oils (synthetic:: M1 is factory fill). Unless you are visiting race tracks or doing serious backroad apex straifing, the factroy oil is just fine. If you do happen to excede the above, then look for an oil with an HTHS number above 3.6. There are several in the xW-30 weight grades, and lots in teh thin end of the xW-40 range.

 

[Ryan00TJ]

My LS1 does not slap nor have I ever heard one that did. I'm around them quite a bit too. I think the topic has been vastly overblown in relation to how many actually have piston slap and the #'s produced.

 

[JMM]

My 2005 GTO LS2 has no piston slap whatsoever. I use Mobil 5W30. FYI: My last car was an 04 Mustang GT 4.6...that thing had the worst piston slap until warm...was sort of embarassing.

 

[Mr Nice]

JMM,

Did you try different weights (0w30, 10w30, 10w40) of oil in your 4.6 Mustang ?

 

[JMM]

LT4 Vette
I tried 0w30, 5w30, Amsoil, GC, Motorcraft...was same with all.