Piston Slap...
11-08-2008, 09:43 PM
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Piston Slap... So I've done some searching and came up with it only occurs in LS1's. Not LS2+, just the first engine. Why is it only present in LS1's? There can't be so much different aside from more cubes, different heads/cam and a few other things?
So what's the deal? Shouldn't there be a way to eliminate it?
So what's the deal? Shouldn't there be a way to eliminate it?
11-09-2008, 09:58 AM
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So I've done some searching and came up with it only occurs in LS1's. Not LS2+, just the first engine. Why is it only present in LS1's? There can't be so much different aside from more cubes, different heads/cam and a few other things?
So what's the deal? Shouldn't there be a way to eliminate it?
So what's the deal? Shouldn't there be a way to eliminate it?
No biggie really, the noise goes away once it's warmed up.
GC 0W30 is thicker/heavier than M1 5W30. Personally, I use M1 0W40 in both my LS1s.
11-09-2008, 10:37 AM
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http://www.upmpg.com/tech_articles/motoroil_viscosity/
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11-09-2008, 10:56 AM
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Thats not really possible. Oil companies have to adhere to strict standards to rate their oil viscosity.
http://www.upmpg.com/tech_articles/motoroil_viscosity/
http://www.upmpg.com/tech_articles/motoroil_viscosity/
I suggest you do more extensive research.
There is a range that any oil can fall in to be sold as a "30" weight. CST rating on GC 0W30 is greater than M1 5W30, hence the GC 0W30 is thicker. GC is on the thick end of a 30 weight, while M1 is on the thin end.
11-09-2008, 11:01 AM
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**** I use the same oil (German Castrol 0w30) I still have piston slap. When I was using 5w30 castrol it was not that bad during cold start up. I think I'm switching back to 5w30 Castrol.
11-09-2008, 11:25 AM
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I use straight up 10-30 Valvoline in my 98' and pretty much hear no piston slap at all.
I think there is a difference in rings maybe within the 4 production years.
I think there is a difference in rings maybe within the 4 production years.
11-09-2008, 12:37 PM
#11
I don't understand what you guys are calling Piston Slap. If your Engine is running without a problem, then you should not have any Piston slap at all.
I spun a Bearing in my Stroker and that caused me to have Piston Slap cause the proper tolerances were no longer being met. When I pulled the Head off, I could see the marks where the Piston was slapping the Head, and it made the very distinct sound too..
Someone explain to me what you guys are calling "Piston Slap" cause I don't see it happening if everything is running good..
I spun a Bearing in my Stroker and that caused me to have Piston Slap cause the proper tolerances were no longer being met. When I pulled the Head off, I could see the marks where the Piston was slapping the Head, and it made the very distinct sound too..
Someone explain to me what you guys are calling "Piston Slap" cause I don't see it happening if everything is running good..
11-09-2008, 12:42 PM
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The slap came when GM started cutting costs. They calibrated their machines, but it seems they cut back on quality control. It's the same mode of thinking that caused them to use the 10bolt behind an LS1, use cheap cracking plastic on T/A door panels, use resin intakes, etc. It's all about their bottom line.
According to the CNBC special, it's a whole new GM. We'll have to wait til the 5th gen to see I guess...
According to the CNBC special, it's a whole new GM. We'll have to wait til the 5th gen to see I guess...
11-09-2008, 02:43 PM
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What's wrong with the LS1/6 intakes? The material is DuPont Nylon 66. Not cheap stuff. I don't see any issues there.
Not the early cars, it's usually with the later cars. I beleive there was a ring change in '01. It seems that the '01+ cars slap more. My '98 is dead quiet. My '99 & '00 were pretty quiet too. My '02 has a healthy case of slap though.
It's the same sound that every GM 3.1L V6 has as well. They are the worst.
It's the same sound that every GM 3.1L V6 has as well. They are the worst.
11-10-2008, 12:18 PM
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Well, if this unnecessarily loud piston slap destroys my motor, I guess I'll be going for the LS2 swap.
No there's no real way to eliminate it or even quiet it down other than oil?
No there's no real way to eliminate it or even quiet it down other than oil?
11-10-2008, 02:06 PM
#19
Oil really won't even stop it. SOMETIMES Seafoam helps by cleaning built up carbon from the piston skirt. What you hear is the piston rocking in the bore and it quits when warm because the piston expands and then fits the bore with tighter tolerances. It is harmless and only an annoyance. Older (60's/70's) Mopars were also notorious for this. There is more info on this I just don't wanna post too long. The 5.3 in my 99 slaps so I did a bunch of research when I first got it several years ago. If you wanna get the **** scared outta you go to the pistonslap.com website
It is BS though or they would have won a class action lawsuit against GM.
It is BS though or they would have won a class action lawsuit against GM.
11-10-2008, 04:02 PM
#20
Oil really won't even stop it. SOMETIMES Seafoam helps by cleaning built up carbon from the piston skirt. What you hear is the piston rocking in the bore and it quits when warm because the piston expands and then fits the bore with tighter tolerances. It is harmless and only an annoyance.