Do not worry about piston slap, as you get older you cant even hear yourself break wind, so whats a little slap, unless your girlfriend slaps you, then u gotta pick up your false teeth,imho.
Piston slap at 82,000 miles ???
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Heck-early pistons were even iron=they've been playing with materials and the aluminum alloys forever and now the chemists with the coatings. It's good to do this work, but I wish 'we' weren't used as the 'proving ground' for it-after all, the manufacturers have their own! I still like cast iron blocks/heads, but the weight savings dictate otherwise. I was grumbly when they first added aluminum heads to the iron blocks and had all kinds of head gasket issues=the two metals expand contrct differently=sure, but the head gaskets weren't initially up to this new task and lots blown.
Originally Posted By: Koz1
http://www.pistonslap.com/experts.htm
One way to check for piston slap: Remove three spark plugs, leaving number one in place. Crank the engine over until you feel the resistance of number one piston coming up on compression. Crank against compression until the piston is about half way up the cylinder. Now using the fan, rock the crankshaft back and forth and listen for a metallic knocking sound. If you hear a knock, you have piston slap and the only way out is to rebuild the engine.
So just rebuild it before it gets worse and causes even more scoring more ticks more fuel and oil consumption.
Loose tolerances and pistons built up wrong?
What is going on with GM these days?
That is a slanderous website, It has been around for years. The method mentioned will not work on any modern engine with fan clutches/electric fans....That may work on old-worn out Cast Piston engines with a ton of cylinder bore taper, But not on this engine!
I have torn down several LS based engines with piston slap, I have yet to find anything wrong, Bores are round & straight, Pistons check out within tolerance, Ring Gap is impressive for a mass produced engine, All bearings "plastigage" perfect.
http://www.pistonslap.com/experts.htm
One way to check for piston slap: Remove three spark plugs, leaving number one in place. Crank the engine over until you feel the resistance of number one piston coming up on compression. Crank against compression until the piston is about half way up the cylinder. Now using the fan, rock the crankshaft back and forth and listen for a metallic knocking sound. If you hear a knock, you have piston slap and the only way out is to rebuild the engine.
So just rebuild it before it gets worse and causes even more scoring more ticks more fuel and oil consumption.
Loose tolerances and pistons built up wrong?
What is going on with GM these days?
That is a slanderous website, It has been around for years. The method mentioned will not work on any modern engine with fan clutches/electric fans....That may work on old-worn out Cast Piston engines with a ton of cylinder bore taper, But not on this engine!
I have torn down several LS based engines with piston slap, I have yet to find anything wrong, Bores are round & straight, Pistons check out within tolerance, Ring Gap is impressive for a mass produced engine, All bearings "plastigage" perfect.
Not really an issue. The three 3400-powered vans we had in the family at one point were all quite slappy when warming up. My brother's was the worst. It sounded like a bucket of marbles loose in the engine when the weather was cold and it had been sitting all night. The van drove itself to the junkyard merrily slapping away.
Every GM engine I have ever had makes all sorts of noise but runs forever.
I would think piston slap would disappear under load, are you sure this isn't a cracked exhaust manifold or maybe a lifter that's a bit sticky?
I would think piston slap would disappear under load, are you sure this isn't a cracked exhaust manifold or maybe a lifter that's a bit sticky?
If you can deal with the noise, that's really the extent of the problem. Just ignore it, honestly.
We have a 5.3L truck at work with like 390K mi on it now...original engine. The last time I drove this truck, the low oil level warning came on. When I got it back to work, it was two quarts low on oil. If it slaps, I haven't noticed, but it usually has been driven around before I use it (I just use it for short trips when I need to). Also, there is a blend door hammering away in the dash that could be hiding any piston slap.
I have never seen a 4.8 or 5.3 that was killed due to piston slap. I have seen them die of other, totally unrelated causes.
We have a 5.3L truck at work with like 390K mi on it now...original engine. The last time I drove this truck, the low oil level warning came on. When I got it back to work, it was two quarts low on oil. If it slaps, I haven't noticed, but it usually has been driven around before I use it (I just use it for short trips when I need to). Also, there is a blend door hammering away in the dash that could be hiding any piston slap.
I have never seen a 4.8 or 5.3 that was killed due to piston slap. I have seen them die of other, totally unrelated causes.
piston slap is usually heard during warm up it maybe the plugs not tight enough
Something to take up the slack between the piston skirt and the cylinder wall might stop the slapping........but what could that be?........oh yeah, I know.......THICKER OIL.
Originally Posted By: Merkava_4
Something to take up the slack between the piston skirt and the cylinder wall might stop the slapping........but what could that be?........oh yeah, I know.......THICKER OIL.
How exactly would that help.
The only time it's an issue is when engine is cold,which means the oil is cold,which means it's too thick to splash up the cylinder wall.
So nope. Thicker oil isn't gonna help.
Try again.
Something to take up the slack between the piston skirt and the cylinder wall might stop the slapping........but what could that be?........oh yeah, I know.......THICKER OIL.
How exactly would that help.
The only time it's an issue is when engine is cold,which means the oil is cold,which means it's too thick to splash up the cylinder wall.
So nope. Thicker oil isn't gonna help.
Try again.
Originally Posted By: Clevy
How exactly would that help.
The only time it's an issue is when engine is cold,which means the oil is cold,which means it's too thick to splash up the cylinder wall.
So nope. Thicker oil isn't gonna help.
Try again.
HA HA!! I knew you couldn't do it!! I was supposed to be on your ignore list!!
You're weak dude!! Weak I say!
How exactly would that help.
The only time it's an issue is when engine is cold,which means the oil is cold,which means it's too thick to splash up the cylinder wall.
So nope. Thicker oil isn't gonna help.
Try again.
HA HA!! I knew you couldn't do it!! I was supposed to be on your ignore list!!
You're weak dude!! Weak I say!
Instead of acting like a 5-year old, how about explaining your point about how oil weight will affect piston slap? Or do you just post for no reason whatsoever?
Originally Posted By: Merkava_4
Originally Posted By: Clevy
How exactly would that help.
The only time it's an issue is when engine is cold,which means the oil is cold,which means it's too thick to splash up the cylinder wall.
So nope. Thicker oil isn't gonna help.
Try again.
HA HA!! I knew you couldn't do it!! I was supposed to be on your ignore list!!
You're weak dude!! Weak I say!
Originally Posted By: Merkava_4
Originally Posted By: Clevy
How exactly would that help.
The only time it's an issue is when engine is cold,which means the oil is cold,which means it's too thick to splash up the cylinder wall.
So nope. Thicker oil isn't gonna help.
Try again.
HA HA!! I knew you couldn't do it!! I was supposed to be on your ignore list!!
You're weak dude!! Weak I say!
Originally Posted By: clinebarger
Originally Posted By: Koz1
http://www.pistonslap.com/experts.htm
One way to check for piston slap: Remove three spark plugs, leaving number one in place. Crank the engine over until you feel the resistance of number one piston coming up on compression. Crank against compression until the piston is about half way up the cylinder. Now using the fan, rock the crankshaft back and forth and listen for a metallic knocking sound. If you hear a knock, you have piston slap and the only way out is to rebuild the engine.
So just rebuild it before it gets worse and causes even more scoring more ticks more fuel and oil consumption.
Loose tolerances and pistons built up wrong?
What is going on with GM these days?
That is a slanderous website, It has been around for years. The method mentioned will not work on any modern engine with fan clutches/electric fans....That may work on old-worn out Cast Piston engines with a ton of cylinder bore taper, But not on this engine!
I have torn down several LS based engines with piston slap, I have yet to find anything wrong, Bores are round & straight, Pistons check out within tolerance, Ring Gap is impressive for a mass produced engine, All bearings "plastigage" perfect.
I was poking at the subject.
No scoring like described in the Tech order, then its ok as indicated, if it is scored needs new pistons according to GMs own Tech-notes. If its horribly scored you would need either overbore or new block to fix it right.
Or http://certechgels.com/ Im no mechanic please tell it like it is on how to fix a badly scored cylinder.
Its good to know engines with the slap are not all scored.
Slap wastes energy, fuel and engine oil.
The tolerances from GM sound sloppy if it leads to alot of slap in alot of engines?
Originally Posted By: Koz1
http://www.pistonslap.com/experts.htm
One way to check for piston slap: Remove three spark plugs, leaving number one in place. Crank the engine over until you feel the resistance of number one piston coming up on compression. Crank against compression until the piston is about half way up the cylinder. Now using the fan, rock the crankshaft back and forth and listen for a metallic knocking sound. If you hear a knock, you have piston slap and the only way out is to rebuild the engine.
So just rebuild it before it gets worse and causes even more scoring more ticks more fuel and oil consumption.
Loose tolerances and pistons built up wrong?
What is going on with GM these days?
That is a slanderous website, It has been around for years. The method mentioned will not work on any modern engine with fan clutches/electric fans....That may work on old-worn out Cast Piston engines with a ton of cylinder bore taper, But not on this engine!
I have torn down several LS based engines with piston slap, I have yet to find anything wrong, Bores are round & straight, Pistons check out within tolerance, Ring Gap is impressive for a mass produced engine, All bearings "plastigage" perfect.
I was poking at the subject.
No scoring like described in the Tech order, then its ok as indicated, if it is scored needs new pistons according to GMs own Tech-notes. If its horribly scored you would need either overbore or new block to fix it right.
Or http://certechgels.com/ Im no mechanic please tell it like it is on how to fix a badly scored cylinder.
Its good to know engines with the slap are not all scored.
Slap wastes energy, fuel and engine oil.
The tolerances from GM sound sloppy if it leads to alot of slap in alot of engines?
My muffled engines with forged pistons -and commensurate relatively generous ambient temperature piston-to-wall clearances-
serve as audible reminders of the engineered-in strength, goodness and durability contained within.
Don’t know why some manufacturers (e.g., GM) have such a tough time fitting ‘silent’ pistons though.
Snug cast hypereutectic have a place in road-going machines but a little slap on occasion makes me feel manly.
serve as audible reminders of the engineered-in strength, goodness and durability contained within.
Don’t know why some manufacturers (e.g., GM) have such a tough time fitting ‘silent’ pistons though.
Snug cast hypereutectic have a place in road-going machines but a little slap on occasion makes me feel manly.
Originally Posted By: kschachn
Instead of acting like a 5-year old, how about explaining your point about how oil weight will affect piston slap? Or do you just post for no reason whatsoever?
Oh that's right .... we got a topic to discuss.
My theory about thicker oil is that it will leave a thicker film on the cylinder wall as well as the piston skirt for the next start up. It will also fill in that extra space between the piston skirt and the cylinder wall during operation. Having the oil already there before you turn the key is better than having a thin oil that gets there quick after you turn the key. That's how engine assembly lube works and your engine builders wouldn't want to start a brand new engine without it. That 5W-20 you guys use drains completely off everything after you shut the engine down and goes straight to the pan.
Some engines need thicker oil regardless of what the engineers say. I doubt they designed the engine on purpose to have piston slap; that was a screwup on their part. They should have put in offset piston pins instead of having them on center. Offset piston pins would prevent the piston from wobbling in the cylinder bore causing that slap. Either that or they should've had longer piston skirts.
Instead of acting like a 5-year old, how about explaining your point about how oil weight will affect piston slap? Or do you just post for no reason whatsoever?
Oh that's right .... we got a topic to discuss.
My theory about thicker oil is that it will leave a thicker film on the cylinder wall as well as the piston skirt for the next start up. It will also fill in that extra space between the piston skirt and the cylinder wall during operation. Having the oil already there before you turn the key is better than having a thin oil that gets there quick after you turn the key. That's how engine assembly lube works and your engine builders wouldn't want to start a brand new engine without it. That 5W-20 you guys use drains completely off everything after you shut the engine down and goes straight to the pan.
Some engines need thicker oil regardless of what the engineers say. I doubt they designed the engine on purpose to have piston slap; that was a screwup on their part. They should have put in offset piston pins instead of having them on center. Offset piston pins would prevent the piston from wobbling in the cylinder bore causing that slap. Either that or they should've had longer piston skirts.
But piston slap has been around forever, way before -20 oils even became available.. And my Accord suffers from it greatly, and I've tried every oil grade up to and including 20W-50 with no effect.
And it doesn't drain completely off. Do you know how completely it can drain off though no matter what the grade?
Originally Posted By: Merkava_4
My theory about thicker oil is that it will leave a thicker film on the cylinder wall as well as the piston skirt for the next start up. It will also fill in that extra space between the piston skirt and the cylinder wall during operation. Having the oil already there before you turn the key is better than having a thin oil that gets there quick after you turn the key. That's how engine assembly lube works and your engine builders wouldn't want to start a brand new engine without it. That 5W-20 you guys use drains completely off everything after you shut the engine down and goes straight to the pan.
Some engines need thicker oil regardless of what the engineers say. I doubt they designed the engine on purpose to have piston slap; that was a screwup on their part. They should have put in offset piston pins instead of having them on center. Offset piston pins would prevent the piston from wobbling in the cylinder bore causing that slap. Either that or they should've had longer piston skirts.
And it doesn't drain completely off. Do you know how completely it can drain off though no matter what the grade?
Originally Posted By: Merkava_4
My theory about thicker oil is that it will leave a thicker film on the cylinder wall as well as the piston skirt for the next start up. It will also fill in that extra space between the piston skirt and the cylinder wall during operation. Having the oil already there before you turn the key is better than having a thin oil that gets there quick after you turn the key. That's how engine assembly lube works and your engine builders wouldn't want to start a brand new engine without it. That 5W-20 you guys use drains completely off everything after you shut the engine down and goes straight to the pan.
Some engines need thicker oil regardless of what the engineers say. I doubt they designed the engine on purpose to have piston slap; that was a screwup on their part. They should have put in offset piston pins instead of having them on center. Offset piston pins would prevent the piston from wobbling in the cylinder bore causing that slap. Either that or they should've had longer piston skirts.
Originally Posted By: Koz1
I was poking at the subject.
No scoring like described in the Tech order, then its ok as indicated, if it is scored needs new pistons according to GMs own Tech-notes. If its horribly scored you would need either overbore or new block to fix it right.
Or http://certechgels.com/ Im no mechanic please tell it like it is on how to fix a badly scored cylinder.
Its good to know engines with the slap are not all scored.
Slap wastes energy, fuel and engine oil.
The tolerances from GM sound sloppy if it leads to alot of slap in alot of engines?
What badly scored cylinder?? You are assuming cold piston slap automatically means Bore damage, High emissions, & Oil consumption.
This thread is about a Gen III LS engine, Snow me one with a bad cylinder caused by the Hypereutectic pistons making noise when cold?
I for one never assumed the OP's issue is Piston Slap. Or anything at all is wrong.
He worked on the truck right before the noise appeared, People develop super human hearing after any repair is performed.
I was poking at the subject.
No scoring like described in the Tech order, then its ok as indicated, if it is scored needs new pistons according to GMs own Tech-notes. If its horribly scored you would need either overbore or new block to fix it right.
Or http://certechgels.com/ Im no mechanic please tell it like it is on how to fix a badly scored cylinder.
Its good to know engines with the slap are not all scored.
Slap wastes energy, fuel and engine oil.
The tolerances from GM sound sloppy if it leads to alot of slap in alot of engines?
What badly scored cylinder?? You are assuming cold piston slap automatically means Bore damage, High emissions, & Oil consumption.
This thread is about a Gen III LS engine, Snow me one with a bad cylinder caused by the Hypereutectic pistons making noise when cold?
I for one never assumed the OP's issue is Piston Slap. Or anything at all is wrong.
He worked on the truck right before the noise appeared, People develop super human hearing after any repair is performed.
Originally Posted By: kschachn
But piston slap has been around forever, way before -20 oils even became available.. And my Accord suffers from it greatly, and I've tried every oil grade up to and including 20W-50 with no effect.
And it doesn't drain completely off. Do you know how completely it can drain off though no matter what the grade?
Originally Posted By: Merkava_4
My theory about thicker oil is that it will leave a thicker film on the cylinder wall as well as the piston skirt for the next start up. It will also fill in that extra space between the piston skirt and the cylinder wall during operation. Having the oil already there before you turn the key is better than having a thin oil that gets there quick after you turn the key. That's how engine assembly lube works and your engine builders wouldn't want to start a brand new engine without it. That 5W-20 you guys use drains completely off everything after you shut the engine down and goes straight to the pan.
Some engines need thicker oil regardless of what the engineers say. I doubt they designed the engine on purpose to have piston slap; that was a screwup on their part. They should have put in offset piston pins instead of having them on center. Offset piston pins would prevent the piston from wobbling in the cylinder bore causing that slap. Either that or they should've had longer piston skirts.
Oh come now, you should know Merk is not one to let facts cloud his judgement...
But piston slap has been around forever, way before -20 oils even became available.. And my Accord suffers from it greatly, and I've tried every oil grade up to and including 20W-50 with no effect.
And it doesn't drain completely off. Do you know how completely it can drain off though no matter what the grade?
Originally Posted By: Merkava_4
My theory about thicker oil is that it will leave a thicker film on the cylinder wall as well as the piston skirt for the next start up. It will also fill in that extra space between the piston skirt and the cylinder wall during operation. Having the oil already there before you turn the key is better than having a thin oil that gets there quick after you turn the key. That's how engine assembly lube works and your engine builders wouldn't want to start a brand new engine without it. That 5W-20 you guys use drains completely off everything after you shut the engine down and goes straight to the pan.
Some engines need thicker oil regardless of what the engineers say. I doubt they designed the engine on purpose to have piston slap; that was a screwup on their part. They should have put in offset piston pins instead of having them on center. Offset piston pins would prevent the piston from wobbling in the cylinder bore causing that slap. Either that or they should've had longer piston skirts.
Oh come now, you should know Merk is not one to let facts cloud his judgement...
Originally Posted By: FL_Rob
Hence,..this.
www.bobistheoilguy.com/forums/ubbthreads.php/topics/3569537
Yes, this.
The Mobil 1 Turbo Diesel Truck stopped my 2003 5.3L from "clacking". Not "slapping". Started it again outside in 15F weather & purpously left the door wide open to listen carefully. NO NOISE. GONE. The Mobil 1 Turbo Diesel Truck has been in for 2,000 miles, btw.
I previously owned a 2000 5.3L that had piston slap. I know what piston slap is, and on my current 5.3L, it was not "slapping".
OP: Put in Mobil 1 Turbo Diesel Truck, run it some and report back with your results.
Please PM me so I am sure to see it.
Hence,..this.
www.bobistheoilguy.com/forums/ubbthreads.php/topics/3569537
Yes, this.
The Mobil 1 Turbo Diesel Truck stopped my 2003 5.3L from "clacking". Not "slapping". Started it again outside in 15F weather & purpously left the door wide open to listen carefully. NO NOISE. GONE. The Mobil 1 Turbo Diesel Truck has been in for 2,000 miles, btw.
I previously owned a 2000 5.3L that had piston slap. I know what piston slap is, and on my current 5.3L, it was not "slapping".
OP: Put in Mobil 1 Turbo Diesel Truck, run it some and report back with your results.
Please PM me so I am sure to see it.
Originally Posted By: Turk
Originally Posted By: FL_Rob
Hence,..this.
www.bobistheoilguy.com/forums/ubbthreads.php/topics/3569537
Yes, this.
The Mobil 1 Turbo Diesel Truck stopped my 2003 5.3L from "clacking". Not "slapping". Started it again outside in 15F weather & purpously left the door wide open to listen carefully. NO NOISE. GONE. The Mobil 1 Turbo Diesel Truck has been in for 2,000 miles, btw.
I previously owned a 2000 5.3L that had piston slap. I know what piston slap is, and on my current 5.3L, it was not "slapping".
OP: Put in Mobil 1 Turbo Diesel Truck, run it some and report back with your results.
Please PM me so I am sure to see it.
Might be short lived. I ran/am running a HDEO 10w30 in the 3400 powered Equinox in my sig. It pretty much made the cold "clacking" go away, until about 3700-4000 miles later on the oil it's back. I'm tired of worrying about it, lol. Seems it is a GM thing, was gonna run a 40wt, but I'm just going to stick with the normal regimen. It's got about 6500 on the oci as of now.
Originally Posted By: FL_Rob
Hence,..this.
www.bobistheoilguy.com/forums/ubbthreads.php/topics/3569537
Yes, this.
The Mobil 1 Turbo Diesel Truck stopped my 2003 5.3L from "clacking". Not "slapping". Started it again outside in 15F weather & purpously left the door wide open to listen carefully. NO NOISE. GONE. The Mobil 1 Turbo Diesel Truck has been in for 2,000 miles, btw.
I previously owned a 2000 5.3L that had piston slap. I know what piston slap is, and on my current 5.3L, it was not "slapping".
OP: Put in Mobil 1 Turbo Diesel Truck, run it some and report back with your results.
Please PM me so I am sure to see it.
Might be short lived. I ran/am running a HDEO 10w30 in the 3400 powered Equinox in my sig. It pretty much made the cold "clacking" go away, until about 3700-4000 miles later on the oil it's back. I'm tired of worrying about it, lol. Seems it is a GM thing, was gonna run a 40wt, but I'm just going to stick with the normal regimen. It's got about 6500 on the oci as of now.
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