GroundControl

What one of those TSB's is saying is that in these engines, they eliminate the skirts of the piston to lower the weight of the rotating assembly... well, the skirt always has a slightly larger diameter than the top half of the piston - when you install a piston, the skirt is a definetely tighter going in then the top half... so it makes sense that they slap.

01 Silverado

All of those TSB's say the piston slap is worse and only audible at initial start-up. Well, mine has been there since day one and is a LOT worse when the engine heats up! It sounds like a diesel if the temp gets 180-200 degrees. Cant wait to be out of college and have a real job, I will hopefully have a setup like Parish with a 408 stroker in it.
Piston slap!

CARAZYCUTER 4.8

a peice of info for you guys.......
I know that on certain year model 6.0 (I believe 2000-2002) GM has been offering godwill policies in the way of extended service agreements or loyalty money for the noise. I personally believe that this is an issue that GM should resolve with customers.I get more complaints & headaches from this than any individual should have to deal with. We have been told that if the noise continues for more than 2-3 minutes after start-up then replace the pistons. How do you justify to a customer that the just spent a small fortune on a new vehicle & the noise is ok if it is only for a couple minutes but anymore than that we will replace the pistons....... They should compensate us (the dealership) for having to listen to complaints all day

2001 HD

My 01 6.0 does it on start-up. Also known as CSK (Cold Start Knock) in some circles.
After writing a polite letter to GM customer service, I received reimbursment for the GMPP warranty and was issued a free full powertrain warranty (not just a letter on the engine).

Personally it doesn't bother me too much. It did at first and I wish it didn't do it, but it hasn't gotten any worse. It uses about 1/2 qt every 3K miles with fixed orifice PCV valve. Some days it hardly does it at all, depending on outside temperature, miles since last oil change (mobil 1), etc. I have not heard of any engine failures due to this problem on stock engines. Some people that have power adders have blown them.
I'm keeping the truck anyway. It still runs like an SOB.

There is another TSB out about the oil pump o-ring being cut causing aireation of the oil and the engine continues ticking, knocking after warm. I don't have the number handy, but maybe someone else does.

CARAZYCUTER 4.8

[

There is another TSB out about the oil pump o-ring being cut causing aireation of the oil and the engine continues ticking, knocking after warm. I don't have the number handy, but maybe someone else does.


[/QUOTE]
I have that tsb, here it is
Engine Knock or Lifter Noise (Replace O-Ring) #02-06-01-038 - (12/02/2002)
Engine Knock or Lifter Noise (Replace O-Ring)
2001-2002 Chevrolet Camaro

2001-2003 Chevrolet Corvette

2001-2002 Pontiac Firebird

2002-2003 Cadillac Escalade, Escalade EXT

2000-2003 Chevrolet Suburban, Tahoe

2001-2003 Chevrolet Silverado

2002-2003 Chevrolet Avalanche

2000-2003 GMC Yukon, Yukon XL

2001-2003 GMC Sierra

with 4.8L, 5.3L, 5.7L or 6.0L V8 Engine (VINs V, T, Z, G, S, N, U -- RPOs LR4, LM7, L59, LS1, LS6, LQ9, LQ4)

Condition
Some customers may comment on an engine tick noise. The distinguishing characteristic of this condition is that it likely will have been present since new, and is typically noticed within the first 161-322 km (100-200 mi). The noise may often be diagnosed as a collapsed lifter. Additionally, the noise may be present at cold start and appear to diminish and then return as the engine warms to operating temperature. This noise is different from other noises that may begin to occur at 3219-4828 km (2000-3000 mi).

Cause
The O-ring seal between the oil pump screen and the oil pump may be cut, causing aeration of the oil.

Correction
Inspect the O-ring seal and replace as necessary. Use the applicable part number listed below. Refer to the Engine Mechanical sub-section of the appropriate Service Manual.

Parts Information
Part Number
Description
Qty

12557752
Seal-O/Pmp (O-ring)

(F and Y Cars)
1

12563963
Seal-O/Pmp (O-ring)

(C/K Trucks)
1


Parts are currently available from GMSPO.

Warranty Information
For vehicles repaired under warranty, use:

Labor Operation
Description
Usage
Labor Time

J1060
Pickup Tube and Screen - Replace
F Car
3.7 hrs

Y Car
4.3 hrs

C Truck
1.3 hrs

K Truck
2.1 hrs

shandy294

Amen to that!

shandy294

Interesting topic. I'm trying to picture pistons with no skirts...they must have some skirt....shorter than older styles?
My 4.8 (5k mi) makes a slight ticking sound at idle after 5 min or so. I was told by a radio guru (big time GM fan.too) that's lifter roller noise on the lobes and that a slighter higher oil viscosity oil would quiet it down. I'm using M1 5w-30...heard they make a 0w-40 but harder to find. Next change I might try 4 of 5w-30 and two 15w-50.

Tokez420

mine slaps, crackles, and pops all the time

Sport Side

iTrader: (6)

they extended my warranty till 100k miles.
i used to get it bad on cold mornings. it would do it for about a minute then quit.

NOSjohn

iTrader: (9)

CrazyCutter and/or 2001 HD - where do we write or call to get this powertrain warranty? Thanks!