[brightred G8GT]

yea im up in the boston area and it just started to get cold and heard it on my G8 ....the little tick tick tick you hear for seconds when u start up is nothing more than what us mechanics call "sticky lifters" from sitting in the cold the oils just dranes . so after you start it should go right away if not u may wanna contact your dealer , but this lifter problem is normal in cold temps and happens in lots of other vehicles also ... and if u wanna go with snyth. oil myself i use royal purple its kinda a lot of $ but i believe its worth it anyway ....best of luck to ya's

 

[SLOWHITE]

I know my TBSS has piston slap unitl the engine reaches operating temp plus about 5 minutes. However I am aware that most do it and am not worried. I did run across this bulletin though.

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Service Information 2008 Pontiac G8 | G8 Service Manual | Document ID: 2197751
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#PIP4499: Short Duration Lifter Tick Noise On Cold Or Hot Restart - Aerated Oil In Filter - keywords BQMI - (Oct 7, 2008)


Subject: Short Duration Lifter Tick Noise on Cold or Hot Restart - Aerated Oil in Lifter


Models: 2009 Buick Lacrosse Super, Allure Super (Canada Only)

2007-2009 Buick Rainier

2007-2009 Cadillac CTS-V

2007-2009 Cadillac Escalade

2007-2009 Chevrolet Avalanche, Corvette, Express, Silverado, Suburban, Tahoe, Trail Blazer

2007-2009 Chevrolet Impala, Monte Carlo

2007-2009 GMC Envoy, Savana, Sierra, Yukon

2007-2009 Hummer H2

2008-2009 Hummer H3

2007-2008 Pontiac Grand Prix

2007-2009 Pontiac G8

2007-2009 Saab 97x

With Any of the Following V8 Engine RPOs:

L76, L92, L9H, LC9, LFA, LH6, LH8, LMG, LMF, LS2, LS3, LS4, LS7, LY2, LY5, or LY6




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

Condition/Concern:
Some customers may comment on a short duration lifter tick noise that occurs after start up and can last for up to several minutes. This may be the result of air in the high pressure chamber of the lifter affecting valve train lash. When this occurs, valve closing velocity is increased, which causes the noise. Air can be present in the lifter at shutdown due to an aerated oil condition, or it can be ingested into the lifter during a cold start. Oil aeration level, oil viscosity, time to achieve oil pressure, engine speed, and lifter design all play a part in whether lifter noise is observed. Once air gets into the high pressure chamber, it will slowly be expelled through the very tight clearance of the plunger and body.

Recommendation/Instructions:
If the SI diagnostics do not isolate the cause of this concern, perform a cylinder power balance test with the Tech 2 while listening to the noise.

If the noise is eliminated, or is greatly improved, each time a specific fuel injector is cancelled, there is most likely a concern with the clearance of the related piston pin or piston to cylinder wall.

If there is no change in the noise when canceling the fuel injectors with the Tech 2, the noise is most likely a result of the lifter concern described above. GM product engineering is continuing work with the lubrication group and the lifter suppliers to improve the robustness of the lifter hydraulic system. New lifter designs are currently under evaluation and this P.I. will be updated with additional information as soon as these updated lifters are available in GMSPO. In the meantime, replacing the lifters with the ones in GMSPO stock may repair this noise in many instances.

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.

WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION


© 2008 General Motors Corporation. All rights reserved.

 

[camoeto]

Just curious, has anyone gone to the dealer with this and did they attempt to diagnose/fix?

I also have this issue. Car sounds normal when I start it up, but has an annoying ticking/slapping sound after I start driving it and press the gas pedal even if slightly. After a few minutes of driving it goes away.

I think a modern car should not have these kind of issues.

 

[jeffthenail]

This noise was a huge issue on the other G8 site that finally(TG) was dropped after ,Oh,300 messages.
It was decided that it was a piston clearance issue and that all LS based motors do this. I have 150k on a 99 LS and have had this noise on start-up since 15-20k miles.It goes away within a couple minutes of warm up.
The general consensus was that it was bad but GM would do nothing about it and, once again, guys decided that GM was screwing them over. Like I said before, it was finally dropped and the threads moved on. This info on lifters is very good and maybe the real reason for the noise. I do recommend that everyone warm up some before loading the motor.

 

[rpiotro]

Yes I do. When the temps are below the freezing mark. Not concerned.

Has anybody here stood next to a big bore diesel engine on startup at 0 degrees F? Between diesel knock and piston slap it is deafening!

I know, not a fair comparison. I think the piston slap is just more audible on our engines because of the alloy block. I had a little of it on my '95 Honda. My son inherited that car and drove it hard beyond 200,000 miles and it ran fine. Never used oil either.

 

[therapture]

My 2001 Suburban 5.3l has it on colder days...not real common around here so....still going strong at 115k miles....

Come to think of it...my 1998 Tahoe 5.7l did it, and so did my previous 1995 GMC truck....

It has been a GM staple in these engines for a while....

 

[DZL]

haven't noticed the noise as of yet, but i remote start mine before i jump into it if it's really chilly...

 

[Top-Gun]

Not to beat a dead horse, but I got thinking about this today and I’m wondering if this noise everyone is hearing really is piston slap and not something else. It was really cold here this morning and I noticed a couple things. Right after startup I brought the revs up to about 2500 rpms a few times and didn’t get any noise out of the motor. It wasn’t until I drove away that I got the rattling sound, which only occurs under acceleration when the engine is cold.

This to me doesn’t sound like piston slap. I would think that a loose piston would make noise not only under load, but also when you rev the engine in park or neutral. The typical LSX engine piston slap noise that has been a concern for years occurs on cold startup with no load on the engine (from what I can tell from research anyways). Thoughts?

 

[drewdog]

i heard something similar this morning, it was 10 degrees at the time and I just started the engine.

I think it lasted a minute or so, then eventually went away - then all i heard was the V8 purr that u get when driving in cold weather

 

[-dak-]

Not to beat a dead horse, but I got thinking about this today and I’m wondering if this noise everyone is hearing really is piston slap and not something else. It was really cold here this morning and I noticed a couple things. Right after startup I brought the revs up to about 2500 rpms a few times and didn’t get any noise out of the motor. It wasn’t until I drove away that I got the rattling sound, which only occurs under acceleration when the engine is cold.

This to me doesn’t sound like piston slap. I would think that a loose piston would make noise not only under load, but also when you rev the engine in park or neutral. The typical LSX engine piston slap noise that has been a concern for years occurs on cold startup with no load on the engine (from what I can tell from research anyways). Thoughts?

Interesting observation. I too have a slapping sound that occurs until the engine is up to temperature. It sounds just like my old forged LT1 which is why I assumed it to be piston slap. In that car the piston-to-bore clearance was too wide. In the case of my G8 I only hear it under load. At idle it is imperceptible. Still it sounds like a "loose" piston in the bore.

In my opinion, such a noise has no place in a modern 30K sedan. I hear it for half of my 15 minute commute, both ways. It's going to the dealer on Monday. My fear is that they will say it is "normal". Has anyone successfully fought GM on this? I sure hope they fix this, but the only way to do so is opening up the motor...

 

[redhed]

i seriously doubt you'll get any "help" with this...but you can try ...

 

[-dak-]

Cancelled the dealer appointment today as temps were in the 40s. The noise only lasts a minute or so at those temps. I'll wait for a nice cold day so that they have more time to diagnose.

 

[camoeto]

i seriously doubt you'll get any "help" with this...but you can try ...

Hmmm... I certainly hope that is not a reflection of GM's attitude to warranty repairs in general. I have never owned a GM before the G8, and in my other cars any concern I had was at least thoroughly investigated. In this case it seems like a no brainer when there is a ongoing problem that is well documented and there is TSB that suggests replacing the lifters. Yes, I do think it's a problem, and just because "they all do it" doesn't make it normal. It's like saying all Fords made between 1985 and 2000 will need multiple transmission rebuilds, but it's ok since they all do it. That being said, in my case I'm not even sure I have it since the noise is only when it's cold, is not loud at all, and goes away soon. Could be the hydraulic lifters if anything.

 

[-dak-]

Finally brought the car in to the dealer. After letting it sit for a couple of hours in ~20F the tech said he "could not recreate the customer's complaint". I'm not going to let them off that easily. I'm leaving it at the dealer overnight on Tuesday. I'll take a drive first thing on Wednesday morning. I'm hoping it will be harder for them to not hear it with me in the car.

 

[redhed]

Interesting observation. I too have a slapping sound that occurs until the engine is up to temperature. It sounds just like my old forged LT1 which is why I assumed it to be piston slap. In that car the piston-to-bore clearance was too wide. In the case of my G8 I only hear it under load. At idle it is imperceptible. Still it sounds like a "loose" piston in the bore.

In my opinion, such a noise has no place in a modern 30K sedan. I hear it for half of my 15 minute commute, both ways. It's going to the dealer on Monday. My fear is that they will say it is "normal". Has anyone successfully fought GM on this? I sure hope they fix this, but the only way to do so is opening up the motor...

did gm actually do anything to rectify your "slap" in the lt1? just wondering. and i agree that this should not be happening. i've never had a piston slap problem with any other vehicle i've ever owned/rented. not sure why gm has such a problem with their v8s when nobody else seems to ...

anway, good luck. i'm not gonna pursue mine since it's a rental and will go back to gm anyway in a couple years ...

 

[-dak-]

My LT1 was a rebuild, so no warranty. I had blown the old motor with a turbo setup. That one wasn't GM's fault by any means.

 

[-dak-]

So I finally left the car overnight at the dealer. Yesterday I sat with a tech as we started and drove the car. The piston noise was obvious as day to me. He described it as "marbles" but said it was normal for a cold engine. I said "no way is that normal". I left it overnight again and they were supposed to do a cylinder balance test. Instead they called GM, told them the noise was normal, and GM told them not to do anything. They gave me the car back and said the cold engine noise is normal.

I'm not sure what to do next. One thing is for sure, though. If GM screws me on this my next car will not be a GM product. I'm 40 and the only new cars I've ever purchased were GM. It's really sad that they care so little about their product and their reputation.

I guess I'll call Pontiac customer service and then send a letter. Not expecting much. Sort of depressed about the whole thing. Brand new car, 100K warranty, and it sounds like a worn out 200K engine when cold. :whine:

 

[therapture]

It's normal, and has been for years. My 1994 truck w/ a 350 did it....my 1995 truck with a 350 did it...my 1998 Tahoe with a 350 did it...my 2001 Suburban with a 5.3 still does it at 114k miles, and my G8 does it. None of them EVER had an engine failure and all of them went well over 100k miles before I replaced them (except the G8 obviously, I just got it). Almost all large GM engines do it, it's normal and goes away after a second or two. How many people does it take to show you its NORMAL and will not hurt anything?

I see tons of trucks and cars at my work that do it and that has been over a span of 15+ years in the auto industry. It does not hurt anything, i.e., it's normal.

 

[nikko01]

Seems to me these cars don't like the cold very much. I got the tap tap tap noise once on a cold morning, and have yet to hear it again. And on a very cold morning I was getting a creaking sound from the front end every time I turned the wheel. Both went away after the car warmed up... Seems a lot of people have these issues. Mine is an 08 GT with 600 miles on it so far.

 

[travelphile]

-dak- I don't want to offend anyone being new to the forum, but I think 'normal' is the way to word it. I haven't heard your car, but a 6 liter is more typical to the truck/SUV applications people are used to hearing similar noises in.

I do not work for GM, but am involved with training technicians and can tell you no car company puts novice techs on problems like yours. They put car lovers/geeks like us on these problems and these guys know the feel & sounds of performance engines. There's nothing those guys like better than to find, document & diagnose a true problem. They aren't all trying to screw new car owners.

I'd send your letter to Pontiac asking it to be looked at, but be careful about placing blame.

On a side note - I also visit/tour a LARGE automotive supplier who does valve train development and LOVE hearing the test engines. They all have noise & they are durability tested to the highest degree - let your friends here convince you that normal noise is not unhealthy!