Anyone heard of this new TSB yet?

Service Information
Document ID: 2065710 #PIP4344: Short Duration Cold Start Lifter Tick Noise - keywords 5.3 6.0 cam engine L76 LC9 LFA LH6 LMG LS4 LY5 oil pressure start - (Feb 18, 2008)



Subject:Short Duration Cold Start Lifter Tick Noise



Models:2007-2008 Chevrolet Avalanche, Silverado, Suburban, Tahoe
2007-2008 GMC, Sierra, Yukon
2007-2008 Chevrolet Impala
2007 Chevrolet Monte Carlo
Equipped with the 5.3 or 6.0 Active Fuel Management engines



The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

<A href="http://gsi.xw.gm.com/si/showDoc.do?docSyskey=2065710&from=ns#ss1-2065710">
Condition/Concern:
A customer may comment on a cold start engine tick noise. The noise explained may be an extended duration noise related to AFM (Active Fuel Management) valve lifters. The noise may repeat on subsequent cold starts. Noise will be camshaft speed and may last over 1 minute. Noise will only occur after a cold soak that is greater than four hours in duration.

<A href="http://gsi.xw.gm.com/si/showDoc.do?docSyskey=2065710&from=ns#ss2-2065710">
Recommendation/Instructions:
Complete the current SI diagnostic for any symptom or DTCs found. If an extended duration lifter tick noise has been verified (usually greater than 1 minute), and the noise is considered excessive and repeatable, lifter replacement may be required. To repair this concern all lifters should be replaced with lifters obtained through GMSPO. There is no special part number necessary.

Note: The 6.0L engine, RPO code LFA has been built with updated lifters since 1-28-2008. 6.0 LFA engines built prior to 1-28-2008 may need the lifters replaced if the customer concern is as described in this PI.

Note: If a cold start lifter tick noise has been verified on any other 5.3L or 6.0L AFM engine, lifter replacement may be necessary. These engines (L76 LC9 LH6 LMG LS4 LY5) do not have a build date released for updated lifters.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

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.


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Well mine has been fine, and we just came out of a -35 C (-31 F) cold snap (f'n cold!! )...hopefully it does not become a widespread issue! I did see the TSB and have been listening...

Couple colds starts did have some kind of whining sound, but when the temp gets that low most vehicles make some noise at startup (plugged in or not).

 

My 07 nnbs Has bes getting a tick at start up, but as far as getting worse it isnt. When the truck is cold idiling there is a tick, You can rev it to about 3000rpms and it will go away. oil pressure is good at high rpms and cold idiling. I kinna think its something to do with the aluminum block in the 5.3's but if the 6.0's are doing it to then its probally a defect in the lifters.

 

sounds like maybe a cover up of piston slap

 

Would u think its piston Slap?

 

i mean after you rev it up it quits even after it idles back down its gone. The tick dosent come back untill another cold start up..

 

Well yeah but it could be the cold temp clearances in the lifters, etc. Piston slap has a pretty well known sound...why would they have the dealers replace lifters to fix piston slap???

 

Yea i have heard piston slap, rod knock, and every other sound that a engine can make, I have been around drag racing all my life and seen ever possible may a motor could blow, lock up etc. I have a Stethascope and i can heard it in the cylinder heads. The springs i put in there seem to be a lil noisy though, The bad thing about fixing the noise like this in a NNBS truck with a Factory warranty, The warranty is gone after the cam install and all the other stuff thats been installed. The whole active fuel managment thing is a bunch of bs around here n e ways. i have gotten better gas milage without it. Id say the 8 dod lifters in the motor are weak as ****, I am gonna see what GM does with this and i am going to go from there. It wouldnt bother me to replace the lifters myself. But if it is piston slap, then i will DE-MOD my truck and let the GM dealership deal with it.

 

The AFM is out for debate for sure. Stock it works pretty good in my truck mileage wise (been tuning for it to stay on longer on the highway), but like you said the lifters probably aren't that strong...heavier trucks it seems pretty useless for sure. Once a guy starts modding best bet is probably to replace those 8 with normal lifters and disable the system?

Hopefully your noise is nothing serious...thing is you are tuned into your truck (esp after having parts changed), most customers don't notice things like that (small noises etc) so I'm thinking it would have to be pretty bad for GM to issue that TSB...

 

Yea i agree 100%. Most customers dosent change their oil when they should. let alone check for any strange noises. Dod be ok i think if they could do some more work on it and get it staying in longer on highway. I contacted GM before my cam swap to see what the specs were on the 8 DOD lifters and they wouldnt acknowledge anything on them and said they do not reccomend and performance upgrades on their motors. But It would have probally been smart of me to go ahead and replace the lifters. One thing i have had on my mind...My truck has the all aluminum block, would aluminum dissipate noises better then the steel block?.....
One more thing i wish they would replace the seats in my truck...they collect lint and look awfull. I have the black cloth seats.