Piston Slap: 98-99 vs. 00-02
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My 99 slaps quite a bit when it's cold out for a couple minutes of easy driving. It sounds bad, but it does go away. At 91k miles, I'm not complaining as it doesn't burn but maybe 1/2 quart at most every 3500 miles, and I ran neck and neck with a 03 Cobra that put down 412rwhp with fipk and Borlas.
Jason
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I can't fathom that this is still being talked about. I have NEVER ever heard a healthy a LS1 style motor that had REAL piston Slap, what everone has been hearing for the last 5-6 years is Rhodes lifters that are only on the exhaust side. Thats why when the engine runs for a few minutes it goes away the lifters are pumping up, they bleed out in the beginning to help with emmisions. My buddies 00 never made a sound and his had 18K miles on it. My 01 that i got with 17 miles on it made the sound from day 1. Check with anyone thats swapped out the lifters for comps the sound is gone and never comes back.
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Piston slap noise comes from the bottom of the engine, not the top where you would hear noisy lifters. Either way, it does NOT hurt our motors. Cross hatch is still visible on these things well after 100k miles. Now, the cars where uneven compression has already started surfacing from piston-to-wall clearance being too tight are the 03/04 Cobras. In an effort to stop any piston slap, Ford designed a tight fit for the forged pistons, but IMO, it's starting to backfire on them already... Shame because those 4.6's were built very well otherwise.
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My 80k 01 slaps like mad when cold and hot. I've gotten used to it, kinda. It ain't no lifter tick either. The lack of underhood insulation and WS-6 hood seem to amplify all engine noises though, even the air intake racket. My dad's 02 C5 never makes a sound.
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No piston slap on my 98.
Funny you mention underhood noise, when I rev my engine with the hood closed, its quiet. Had people ask if I had a v8.
As soon as you open the hood and rev it then, its loud as hell... yep its a v8...
Funny you mention underhood noise, when I rev my engine with the hood closed, its quiet. Had people ask if I had a v8.
As soon as you open the hood and rev it then, its loud as hell... yep its a v8...
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Originally Posted by 42NightZ28
I can't fathom that this is still being talked about. I have NEVER ever heard a healthy a LS1 style motor that had REAL piston Slap, what everone has been hearing for the last 5-6 years is Rhodes lifters that are only on the exhaust side. Thats why when the engine runs for a few minutes it goes away the lifters are pumping up, they bleed out in the beginning to help with emmisions. My buddies 00 never made a sound and his had 18K miles on it. My 01 that i got with 17 miles on it made the sound from day 1. Check with anyone thats swapped out the lifters for comps the sound is gone and never comes back.
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Originally Posted by Rebelord
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Try Changing your lifters during a head swap, the sound goes away everytime. If you guys need more proof the 6.0L make the same sound also using a different block and different pistons. But they use the same lifters. And if your hearing a sound deep in the engine you might want to look into Rod knock as true piston slap happens at TDC during the exhaust stroke
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No slap or oil consumption on my 99 F-body.
I replaced the heads, cam, push rods, lifters etc a few years ago. No piston slap or oil consumption before or after the swap.
Consequently, some GM engines just slap and or burn oil; other engines do not. Therefore, "slap" and "oil burn" meet the legal defination of a design defect.
I beleive BMW had a series of engines that had slap. They fixed every one under warranty. That is why BMW is selling lots of cars and GM is almost bankrupt!
I replaced the heads, cam, push rods, lifters etc a few years ago. No piston slap or oil consumption before or after the swap.
Consequently, some GM engines just slap and or burn oil; other engines do not. Therefore, "slap" and "oil burn" meet the legal defination of a design defect.
I beleive BMW had a series of engines that had slap. They fixed every one under warranty. That is why BMW is selling lots of cars and GM is almost bankrupt!
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tick, tick, tick, tick, tick, tick, tick, tick, tick, tick, tick, tick,
2002, Had slap from the dealer, ran 13.1 w/ lid/catback and crap tires w/ 47k. 0w30 gc oil, might switch to Amsoil 5w40 as many people have reported it quieting down the motor. I have slap at cold start, and warm restart.
2002, Had slap from the dealer, ran 13.1 w/ lid/catback and crap tires w/ 47k. 0w30 gc oil, might switch to Amsoil 5w40 as many people have reported it quieting down the motor. I have slap at cold start, and warm restart.
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I have some sort of a noise in my 02 but I wouldn't want to say for sure it's piston slap. It's more of a tick than a slap, and it's not the valve train. It sounds more like the tick originates in the front driver's side from something. I always figured it was a belt idler bearing or a tensioner making the noise or an exhaust tick. The oil I use doesn't affect it. It hasn't caused any problem so I don't worry about it.