Do I have "piston slap" ?

[ScottyBoy]

I have a 2001 Suburban with the 5.3 liter engine. It has right at 65,000 miles on it now. I've owned it for a little over a year now and recently (around November) I noticed it started making a strange noise upon startup. It almost like a pinging sound. The best way to describe it is that it sounds exactly like a deisel engine. But now heres the strange part. It will only do it if it hasnt been started in over 8 hours or so (overnight usually) And it only makes the noise for anout 20-30 seconds, then it sounds fine. Every other time during the day when I start it, I dont hear this noise, it sounds normal. But then I'll hear it again the next morning for the 30 seconds again. Also, the noise seems to be worse (louder) when its colder outside. I did a search on here and it seems several others have similar symptoms as I do and they refer to it as "Piston slap". Is it possible thats what I have? How do I cure it? And do you think this would be covered under an extended warranty? Or would this be like the dreaded steering shaft lube problem and be considered "maintenance"??

[Mark_in_Tulsa]

Well the short answer is, yes.

 

The long answer is, probably so.

[Green_Monster]

Tell him what he's one Johnny!.............PISTON SLAP!

 

GM will say it's normal operation...it's not suppose to hurt performance or longevity. My father has it in his 2001 Burban but I don't have it in my 2006 CC.

[pwall]

Sounds just like my 2002...and many others on this forum.

As in previous posts, that's piston slap. GM says it's normal. yeah right!

[ScottyBoy]

Even though this is "normal", is there any way to cure it, or at least almost cure it?

[pwall]

I just had my truck at the dealership on Thursday. They put in some 'chemical' to remove all the carbon buildup in the engine to help with the piston slap. They didn't charge me for it, which was good.

Didn't make any difference at all.

 

GM says it's normal and doesn't cause any negative effect, except for the embarassment when you drive down your street first thing in the morning and you neighbors are wondering why your $40-60K truck is making so much noise.

[Z71Rider]

Even though this is "normal", is there any way to cure it, or at least almost cure it?

Short of rebuilding your engine and installing some long skirt pistons...likely after doing a .030" bore...no, there is no 'cure'. The pistons in your engine are short skirt design. They are more likely to do the "cock left/cock right" dance (piston slap you hear) while going up and down in the cylinders due to this design. In a short time after startup, they will warm and expand to fill the cylinder bore and stop the cocking action. And the colder the pistons are at startup, the longer it takes them to warm and expand. GM did installed these pistons to create less drag, lower weight, higher performance. Sometime aroung the 05 or 06 model year, they did indeed put longer skirt pistons in the Vortec engines.

 

So, what can you do within reason? First, I use Mobil 1 im my 02 Silverado with the 5.3 and, yes, the slap. I figure the better oil film you have on the cylinder walls, the better chance that the slapping won't scuff the pistons. Second, and this may be the most important thing, let the engine warm up a bit before loading it. And the colder it is, the longer you warm....maybe up to 90 seconds at times. And last, start off easy on your cold start takeoffs...until at least a minute after you stopped hearing the slap.

 

Has anyone out there experienced an engine failure that could be attributed to the slap issue?

[Z71Rider]

Even though this is "normal", is there any way to cure it, or at least almost cure it?

Short of rebuilding your engine and installing some long skirt pistons...likely after doing a .030" bore...no, there is no 'cure'. The pistons in your engine are short skirt design. They are more likely to do the "cock left/cock right" dance (piston slap you hear) while going up and down in the cylinders due to this design. In a short time after startup, they will warm and expand to fill the cylinder bore and stop the cocking action. And the colder the pistons are at startup, the longer it takes them to warm and expand. GM did installed these pistons to create less drag, lower weight, higher performance. Sometime aroung the 05 or 06 model year, they did indeed put longer skirt pistons in the Vortec engines.

 

So, what can you do within reason? First, I use Mobil 1 im my 02 Silverado with the 5.3 and, yes, the slap. I figure the better oil film you have on the cylinder walls, the better chance that the slapping won't scuff the pistons. Second, and this may be the most important thing, let the engine warm up a bit before loading it. And the colder it is, the longer you warm....maybe up to 90 seconds at times. And last, start off easy on your cold start takeoffs...until at least a minute after you stopped hearing the slap.

 

Has anyone out there experienced an engine failure that could be attributed to the slap issue?

 

[Z71Rider]

Even though this is "normal", is there any way to cure it, or at least almost cure it?

Short of rebuilding your engine and installing some long skirt pistons...likely after doing a .030" bore...no, there is no 'cure'. The pistons in your engine are short skirt design. They are more likely to do the "cock left/cock right" dance (piston slap you hear) while going up and down in the cylinders due to this design. In a short time after startup, they will warm and expand to fill the cylinder bore and stop the cocking action. And the colder the pistons are at startup, the longer it takes them to warm and expand. GM did installed these pistons to create less drag, lower weight, higher performance. Sometime aroung the 05 or 06 model year, they did indeed put longer skirt pistons in the Vortec engines.

 

So, what can you do within reason? First, I use Mobil 1 im my 02 Silverado with the 5.3 and, yes, the slap. I figure the better oil film you have on the cylinder walls, the better chance that the slapping won't scuff the pistons. Second, and this may be the most important thing, let the engine warm up a bit before loading it. And the colder it is, the longer you warm....maybe up to 90 seconds at times. And last, start off easy on your cold start takeoffs...until at least a minute after you stopped hearing the slap.

 

Has anyone out there experienced an engine failure that could be attributed to the slap issue?

 

 

Guess I don't know how to use that feature....

[ScottyBoy]

Well I guess its a good thing I have remote start. I just remote start it in the morning and by the time I go outside the piston slap has stopped.

[svensk]

Hmm...On my 2000 I have the squeeky belts at startup, but I don't think I have a piston slap. When I start driving out of my driveway in the morning I can hear a "fan ticking" type noise only when I hit the gas pedal for a short period at low speed. It goes away once I get up past 30mph.

[KB06YUKONXL]

I had a 2002 5.3l Suburban with piston slap. Try some Pennzoil 10w30 oil and see if it quiets it down. It worked for me up here in the Summer. The 10w oil will leaver a thicker oil film on the cylinder wall and should reduce some of the slap at start up. Since it only costs you $20 to try it....why not?

[uncleleo]

I had a 2002 5.3l Suburban with piston slap. Try some Pennzoil 10w30 oil and see if it quiets it down. It worked for me up here in the Summer. The 10w oil will leaver a thicker oil film on the cylinder wall and should reduce some of the slap at start up. Since it only costs you $20 to try it....why not?

 

I had the same with 01 Sierra. Complained to GM and recieved 75000 warranty. I switched to AMSOIL 0w30 (full syn) and the 'ticking' stopped, not immediately, but after a couple months. Now have 72k, runs & sounds great and I attribute it to the AMSOIL.

[george.underwood]

The wife's 02 Sub makes exactly the sound IhatethatbitchKatrina describes. It always goes away within a minute of cold startup. I first noticed it at 30-40K. Now has over 100K and it hasnt gotten any worse that i can tell. I've used only synthetic oil and assume this is prolonging the life somewhat. We also live in middle GA and dont get too much real cold weather.

[Nappers]

I have a 2000 GMC Yukon and it had piston slap when I bought it used in '04 with 68,000 miles on the clock. I switched to Mobil 1 5/30 with Wix/Napa Gold filters and seafoamed it and it purrs like a kitten, no piston slap whatsoever. Sometimes I can't even hear the engine running. 113,000 miles on it now.