Area47

that tsb falls under the 2010+ 6.2's as well.

01WS6/tamu

iTrader: (36)

YUP my 11' developed it once the temps started falling here as well. I'm talking about the noise the TSB describes on cold start at low ambient. BUT: A switch to amsoil 15/40 diesel/marine oil solved it. I've had amsoil 10/30 in it since 5 miles so it's nothing new to the truck. I've had excellent luck with diesel oil in noisy LS engines and it has shut up more than one customers noisy LS.

Allgonoshow

iTrader: (1)

It this the tsb, I couldn't find anything else.
I just copied the top of it.
I suppose my engine could have afm hardware, that is not activated.
My noise is way beyond a tick, sounds like an old Cummings.

Anyway, they are putting pistons in it.

TECHNICAL

Bulletin No.: 10-06-01-007C

Date: February 09, 2011

Subject: Active Fuel Management (AFM) Engine, Valve Lifter Tick Noise at Start Up When Engine Has Been Off for 2 Hours or More (Evaluate Noise and/or Replace Valve Lifters)

Models:
2007 Buick Rainier
2009 Buick LaCrosse Super, Allure Super (Canada Only)
2007 Cadillac Escalade
Built Prior to April 1, 2006 with 6.2L Engine RPO L92 (These engines were built with AFM Hardware but the AFM system was disabled)
2010-2011 Cadillac Escalade, Escalade ESV, Escalade EXT
2007 Chevrolet Monte Carlo
2007-2009 Chevrolet Impala
2007-2011 Chevrolet Avalanche, Silverado, Suburban, Tahoe, TrailBlazer, TrailBlazer EXT
2010-2011 Chevrolet Camaro SS
2007-2011 GMC Envoy, Envoy XL, Sierra, Yukon, Yukon Denali, Yukon XL, Yukon XL Denali
2007-2008 Pontiac Grand Prix
2008-2009 Pontiac G8
2007-2009 Saab 9-7X
Equipped with AFM (Active Fuel Management) and V8 Engine RPO L76, L94, L99, LC9, LFA, LH6, LMG, LS4, LY5 or LZ1

Attention:
This bulletin only applies to the AFM V8 engines listed above. It DOES NOT apply to Non-AFM Engines. If you are dealing with a Non-AFM engine that is experiencing a similar noise, please refer to Engine Mechanical > Diagnostic Information and Procedures
> Symptoms in SI.

Supercede:
This bulletin is being revised to add models. Please discard Corporate Bulletin Number 10-06-01-007B (Section 06 - Engine/Propulsion System).

Condition

Some customers may comment on an engine valve lifter tick noise that occurs after the engine has been shut off for at least two hours. The tick noise may last from two seconds to ten minutes.

1994Vmax

iTrader: (4)

I would doubt that TSB has anything to do with you. My old 09 2500's LY6 had one lifter fall apart and wipe a lobe off the cam. Of course those are not AFM either and there was no TSB that applied there. The dealer swapped in a new long block in this instance. That said they noted that although the engine showed no other signs of abuse the lifters were all in poor shape in the truck. Of course the truck was running like a 2 cylinder John Deere and missing like crazy as well.

It could be ill fitted bores for the pistons as well, or wrist pin noise, or.........

Well we can just keep randomly guessing or wait and see what the diagnosis actually is.

01WS6/tamu

iTrader: (36)

If your truck has a noise that is not right I guarantee that you as the driver knows. I hope they get to the bottom of it it really sucks having problems with a brand new truck.

This bulletin references the noise my truck had and switching to the heavier diesel oil solved it completely.

#01-06-01-028B: Engine Knock on Cold Start - (Oct 3, 2011)
Subject: Engine Knock on Cold Start

Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models
2002 Cadillac Escalade (2WD)
Equipped with 4.8L, 5.3L or 6.0L Engine (RPOs LR4, LM7, L59, LQ4)
2007-2012 Cadillac Escalade Models
2007-2012 Chevrolet Silverado
2007-2012 GMC Sierra, Yukon Denali, Yukon XL Denali
Equipped with 6.2L Engine (RPOs L92, L94, L9H)

This bulletin is being revised to update the Models section. Please discard Corporate Bulletin Number 01-06-01-028A (Section 06 – Engine/Propulsion System).

Some of the above vehicles may exhibit an engine knock noise that begins in the first 19,000-24,000♦km (12,000-15,000♦mi) of use. The knock noise is most often noticed during initial start-up and typically disappears within the first 5-30♦seconds (may last longer in extreme cold temperatures). The noise is usually more noticeable on the initial start-up when the temperature is below 10°C (50°F) and may be more pronounced on the first cold start following a long trip.

This noise may be caused by an interaction between carbon that has formed on the piston, the piston motion and the cylinder wall. GM Powertrain Engineering, and an analysis of engines with this condition, has confirmed that the noise is not detrimental to the performance, reliability or durability of the engine. THIS NOISE DOES NOT HAVE ANY EFFECT ON THE LONGEVITY OF ANY OF THE ENGINE COMPONENTS.

Important: At this time, attempts to repair this condition by replacing the engine assembly or pistons are not recommended.

Please share the information found in this bulletin with customers who inquire about this condition. In the event they have additional questions or concerns, please advise your District Manager Aftersales (U.S.) (in Canada, District Manager - Customer Care and Service Process (DM-CCSP).

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.


WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

Allgonoshow

iTrader: (1)

Great info, I hadn't seen that tsb, I use ALLDATA at work and I'm sure it wasn't on the list.
15/40 is a long way from 5/30. No worry about cold start wear?
I might run a little heavier grade in mine when I get it back.

But, whatever condition caused the noise in my engine, it was outside the typical stuff,
it is severe, they said they are putting pistons and related parts in it.
I hope I find out the the root issue.

Best

Area47

i'll find the tsb number when i go into work monday

Holty

iTrader: (6)

subscribed for root cause determination.

Egghaus

Hmm that TSB is dated about a month prior to the carbon related noise I had with my engine. Why is this only a 6.2 problem?

LS3SSRS

my truck is making ticking noises now too... doesn't matter if its cold or warm, there's a constant ticking noise. gonna have to get it looked at soon... only 4800km