I am fixing to change my oil and I was wondering if there is a oil that will help with piston slap. My car only really does it when you first start it after it has sit all day or all night. Once it has warmed up it doesn't do it any more. It only does it on cold start.

 

My old Pontiac does that too. I tried a number of things and just decided to live with it. Sounds like a diesel when you start it, but it has almost 190K miles now and runs great so other than the obnoxious sound I wouldn't worry about it.

 

You will hear some people say oil brandX fixed their CSK/piston slap but that is total BS. No oil is gonna fix a piston that is loose in the bore. A can of Seafoam through the brake booster or PVC will make it better or get rid of it for a while until the carbon builds back up on the piston skirt.

 

Try 15W-50 Mobil 1.

Russ Kemp

 

I have 0w30 gc in it now with no luck. I have also tried seafoaming it. No difference. Its really not that bad I have heard of a lot worse. It only does it the first time you start it after it has sit over night.

 

Yup, same experience here. Did the GC thing, no difference. Did the Seafoam thing, no difference. I just live with the truck-like tones at first startup. After that it's all good noises coming from under the hood.

 

What's the easiest way to distinguish between a piston slap and a ticking lifter? If they sound identical, then many of us may be mistaking one for the other.

Does the frequency of a lifter tick follow the RPM? Or rather, does a lifter tick go faster with gas?

How much life does a piston slap take away from an engine compared to one without a piston slap?

 

Switched over to Penzoil Platinum 5W-30 last year in a 1999 C5 (66,000 miles) after using Mobil 1 routinely. Made the change just to give it a try as it meets the GM specs and is less expensive at WM too. Was surprised that the piston slap noise was significantly reduced/disappeared upon startup. No, it doesn't fix the problem but apparently did provide a buffer to reduce the typical piston slap noise heard as the vehicle warmed up.

The PP also seems to be much better at reducing volatilization as the normal oil consumption of 1/2 - 3/4 of a quart per 3000 miles ceased -- my driving habits haven't changed. Recently completed a H/C, LS6 intake and headers install which demands even more flogging of the engine and still have very little oil consumption.

Simply my individual experience with this oil and my opinion only, nothing more. Mobil 1 remains an excellent lubricant for these engines. Go to "Bob The Oil Guy" website if you want to delve into all sorts of lubricant related issues. Good luck.

A1

 

That is what I use, plus a 3-qt accu-sump to pre lube the block before cranking it over

 

My buddy put some GC in his car and his piston slap got worse so he switched to what I use (castrol syntec 5W-30) and it quieted down significantly.

My car doesnt have any piston slap that is audible to my ears, I bought it with 49k miles and have always used castrol syntec 5W-30.

Not saying this is the best oil to use or that itll fix everyones problem, just stating my experience with it.

 

GC protects very well, but is does make my car slap worse in the cold. Amsoil 5w40 is one of the quieter oils Ive tried, and has excellent results. Its expensive and can be a pain to get though...

 

Since your car has stock internals use a name brand non-synthetic 30 weight like Castrol. Non-synthetics are less noisy and is what these cars are made to use anyway. If you insist on using synthetic, dont use Mobil 1 as a lot of people on here say their engine is noisy in general with that oil.

 

I went to Mobil 1 0W-40, and the noise doesn't seem as bad. It's definately there, but not too loud.

I've noticed on Honda's with noisey valvetrains that high moly content oils will quiet a cold valvetrain. You might try Redline 10W-30 or 10W-40. It has a lot of moly, and may help out. I would start with the 10W-40 Redline, and if that doesn't fix it, then I would just concede to the piston slap.