got bad piston slap.. Which oil??

**PAT-LS101** · 03-29-2009, 03:22 PM

Im using royal purple 10W30 right now.. what do u guys think is the "best" oil ?? I was going to try Mobil 1 30W??

**sunsetorangess** · 03-29-2009, 04:05 PM

Why 10w 30? How many miles do you have on the car?
J

**Firebirdjones** · 03-29-2009, 04:09 PM

I run 10w-30 in both of our SS's. One has had piston slap forever and the other doesn't have the slightest hint of it.
Luck of the draw I guess, but I can tell you I run the same oil in both so I'd venture to say the oil I'm running has nothing to do with it.

I have heard of people switching from synthetic to regular dino oil (same weight) and the slap is less noticable. Not sure why, I've never tried it myself.

**PAT-LS101** · 03-29-2009, 04:28 PM

Originally Posted by Firebirdjones

I run 10w-30 in both of our SS's. One has had piston slap forever and the other doesn't have the slightest hint of it.
Luck of the draw I guess, but I can tell you I run the same oil in both so I'd venture to say the oil I'm running has nothing to do with it.

I have heard of people switching from synthetic to regular dino oil (same weight) and the slap is less noticable. Not sure why, I've never tried it myself.

Yeah.. I have it pretty bad when it starts up sounds like its going to fall apart but goes away and running for a bit....

**dklowrider** · 03-29-2009, 04:35 PM

Originally Posted by Firebirdjones

I run 10w-30 in both of our SS's. One has had piston slap forever and the other doesn't have the slightest hint of it.
Luck of the draw I guess, but I can tell you I run the same oil in both so I'd venture to say the oil I'm running has nothing to do with it.

I have heard of people switching from synthetic to regular dino oil (same weight) and the slap is less noticable. Not sure why, I've never tried it myself.

i dont know if i buy that oil makes any diff in the piston slap. when i bought this car w/1111,000 it had it, changed oil w/10/30 dino, then couple hundred miles later w/5/30 castrol edge syn., and the noise never changed. its not a condition like noisy bearings or lifters at cold start where oil could make a difference imo. the type of condition that exists which causes the noise is totally different. the ambient temp does seem to play a part in the severity and duration of the piston noise though, which makes sense.

**Firebirdjones** · 03-29-2009, 04:45 PM

Originally Posted by dklowrider

i dont know if i buy that oil makes any diff in the piston slap. when i bought this car w/1111,000 it had it, changed oil w/10/30 dino, then couple hundred miles later w/5/30 castrol edge syn., and the noise never changed. its not a condition like noisy bearings or lifters at cold start where oil could make a difference imo. the type of condition that exists which causes the noise is totally different. the ambient temp does seem to play a part in the severity and duration of the piston noise though, which makes sense.

Just stating what I've been told. Never tried switching myself since I have a pair of 4th gens and only one is doing it. Both use the same oil

Just one of the evils of an LS motor. Pretty common actually.

**Firebirdjones** · 03-29-2009, 04:48 PM

Originally Posted by PAT-LS101

Yeah.. I have it pretty bad when it starts up sounds like its going to fall apart but goes away and running for a bit....

Mine does it cold. After running for a few miles it goes away so I just don't worry about it.

Now if it drops a piston skirt in the pan I might have to do something about it

Honestly I just look at it as a reason to buy a crate motor in the future if it gets to that point.