Piston slap?
12-10-2008, 07:19 AM
#31
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Well about 3 months ago I stated getting a little piston slap...at least that's what I think it is? Only on a cold start and only until temps come up to say ~ 150*. It's a horrible knocking sound that will get louder if I roll on the throttle.
Oil pressure is good, M1 changed every ~3000 miles. Sound about normal? It didn't start after any incident or race or anything like that, it just started doing it.
I have 33K miles on this engine.
Oil pressure is good, M1 changed every ~3000 miles. Sound about normal? It didn't start after any incident or race or anything like that, it just started doing it.
I have 33K miles on this engine.
trever1t,
Hey brotha' I've been doing some spying around in GM's Service Information for you about any related topic to do with your problem. I've found a few bulletins that you may be intrested in. If you want I can try and post them up in this thread (albeit some are lenghty) or if you have a fax nearby, I can fax them to you. PM me and let me know if you'd like me to send some of these to you or if you'd like me to post them up.
12-10-2008, 08:18 AM
#32
yea post them up.....I have a longblock from a 2000 C5 vette in my truck and it is mad loud! The thicker the oil I use, the louder it is! It dont just knock a little, it sounds like someone is banging on the block with a hammer! It has done this for the entire 13,000 miles I have put on it. I changed lifters, cam, valve springs, and nothing made it better. I have heard piston slap in some of these but I have never heard one sound like mine! I think a sleeve has came loose in mine but not really sure, I didnt notice anything when I had the heads off but mighta overlooked it cuz I was thinking it was a lifter problem. O and you can still hear mine making noise after 20 minutes of driving when it is cold out. I did hear a sound clip of a camaro that had some work done to it that sounded like mine......I would guess he has the same issue. I will find out when she blows I guess!
12-11-2008, 12:52 AM
#35
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i tried sea foam. didn't make a difference. i probably should of sucked it up through the vaccuum hose. is that what you did JakeBrake? i put mine directly in the crankcase.
i have lucas oil treatment in my truck right now. that doesn't make a difference either. the temp outside plays a huge role in its severity .
i have lucas oil treatment in my truck right now. that doesn't make a difference either. the temp outside plays a huge role in its severity .
Sucking it through the bake booster vacuum line is what you want to do to get it in the Intake.
12-13-2008, 09:14 AM
#38
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Why don't ALL of them knock? Mine doesn't do it nor a friend's 2000 5.3 but I've heard a 6.0 do it.
I put Sea Foam in the oil once but just for 5 min at idle before changing the oil. I did wonder if it would knock stuff loose and cause problems. It had about 40K when i did it and has had M1 since the first change.
I put Sea Foam in the oil once but just for 5 min at idle before changing the oil. I did wonder if it would knock stuff loose and cause problems. It had about 40K when i did it and has had M1 since the first change.
12-14-2008, 12:02 PM
#40
Sorry man, but the only GEN3/IV engine to use forged pistons is the new 2009 supercharged LS9 ZR1 Vette engine.
Even the supercharged 556hp 2009 Cadillac LSA engine uses cast pistons. As does the 505hp LS7.
Again they're NOT forged, they are a cast hypereutectic cast aluminum desgn. Hypereutectic simply means "High Silicon". The main reason a high silicon cast piston is used...
peace
Hog
Even the supercharged 556hp 2009 Cadillac LSA engine uses cast pistons. As does the 505hp LS7.
Again they're NOT forged, they are a cast hypereutectic cast aluminum desgn. Hypereutectic simply means "High Silicon". The main reason a high silicon cast piston is used...
peace
Hog
Not tryin to say this or that, just lookin for clarification for my own understanding.