dvilin

Duntov7

FYI: Saw this one.....not very close tho'.........

# 99-04-20-002I: Information on Driveline Clunk Noise - (Nov 18, 2014)

Subject: Information on Driveline Clunk Noise

Models: 2015 and Prior GM Passenger Cars and Light Duty Trucks


This Bulletin has been revised to add the 2015 Model Year and remove the Important statement. Please discard Corporate Bulletin Number 99-04-20-002H.

Some customers of vehicles equipped with automatic transmissions may comment that the vehicle exhibits a clunk noise when shifting between Park and Drive, Park and Reverse, or Drive and Reverse. Similarly, customers of vehicles equipped with automatic or manual transmissions may comment that the vehicle exhibits a clunk noise while driving when the accelerator is quickly depressed and then released. Tipping into the throttle after deceleration can also result in some level of clunk as the driveline is loaded in one direction (coast) then with throttle reapply the driveline gets loaded in the opposite direction (drive). On manual transmission vehicles depressing the clutch while in a deceleration immediately releases load on the driveline and may produce a clunk noise as the driveline unloads.
Note : Compare this complaint vehicle to a like vehicle. If the results are the same, this is a normal condition. For additional diagnostic information, refer to the appropriate Service information.

Whenever there are two or more gears interacting with one another, there must be a certain amount of clearance between those gears in order for the gears to operate properly. This clearance or freeplay (also known as lash) can translate into a clunk noise whenever the gear is loaded and unloaded quickly, or whenever the direction of rotation is reversed. The more gears you have in a system, the more freeplay the total system will have.

The clunk noise that owners sometimes hear may be the result of a buildup of freeplay (lash) between the components in the driveline. For example, the potential for a driveline clunk would be greater in a 4-wheel drive or all-wheel drive vehicle than a 2-wheel drive vehicle. This is because in addition to the freeplay from the rear axle gears, the universal joints, and the transmission (common to both vehicles), the 4-wheel drive transfer case gears (and their associated clearances) add additional freeplay to the driveline.

In service, dealers are discouraged from attempting to repair driveline clunk conditions for the following reasons:

^ Comments of driveline clunk are almost never the result of one individual component with excessive lash, but rather the result of the added affect of freeplay (or lash) present in all of the driveline components.

Because all of the components in the driveline have a certain amount of lash by design, changing driveline components may not result in a satisfactory lash reduction.

^ While some owners may find the clunk noise objectionable, this will not adversely affect durability or performance.

HAD2HAV2

B&W, are you inquiring about TSB #14876 for the A8?

Black&White

I plan on confronting Tadge at the Bash about ongoing issues with the A8 and also the T/C replacement issue and the lack of Dealership knowledge to properly repair our A8s. I would like at this time to alert members here of my intentions and ask anyone with an issue or concerns to please email me at the address below. I would like to get a letter with a VIN and the problems you are having and copies of any service you might have had done. Also state your concernes on the issue. I / We will then present him with a file of these letters and documents at the Bash. This is the first call I will be bringing this post up from time to time as a reminder to send me your paperwork. In the PM I will issue you an email address to send your letter and attach any service records to. I will also be staying at the Super 8 across the street in case anyone just wants to drop the papers off the morning of the opening seminar with the engineering team. Thanks.

Edit: Let's do this instead of the Forum PM, email your papers or contact me at this address A8Issues@Gmail.com







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Woodson

Another new thread?

mikez06

SO entertaining, glad I took you off 'ignore', now you go back on!





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Your quote: FYI Tadge is a proven liar. They would say something like that to make sure they don't get a rush of 16 Stingray Z51 orders that they don't have enough parts allocation for and can't fill.
Last edited by Black&White; Today at 09:08 AM. Unquote.

If you believe that, why would you *cough* 'confront' him, duh?










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Black&White

Yup.. Getting lots of response already too. Keep them coming in.

GizmoZ

You plan on "confronting" him? What are you, 12?

Black&White

No, Smart. FYI it won't just be me Now in a Gomer Pile voice SURPRISE SUPRISE!!

Red C8 of Jax

You would think there would be a dealer in the Chicago area that would be able to properly diagnose the problem with the A8 and replace a torque converter. Not that complicated. All it takes is a phone call to GM and they will send the dealer a new torque converter. All replaced under warranty.

Black&White

It's sadly not just me so, since I have done the research and the investigating as a large group we can hopefully make it easier than I have had to get people's cars fixed properly and without fighting GM on approving the warranty work. My issue has nothing to do with the Dealer at all they have diagnosed and told GM they need to replace my transmission and they simply refuse to approve the warranty work and it appears I'm not alone. Well I'm going to GMs G/S coming out party with a nice bag of poo in hand.

SublimeZ06

While I understand your frustration and commend your effort, it likely will do no good. All you will get from that politician is appeasement and oxygen waste.

bd377103

Why do you think Tadge has anything to do with the type of service you're receiving at a local dealership let alone a warranty claim? That is the equivalent to asking Steve Jobs why the Verizon store won't replace a cracked screen on your iphone under warranty ....

Red C8 of Jax

I hope you are successful

Crossed Flags Fan

I hope your approach is a bit more mature than how you've stated it here. "Confronting" (defined as "meet someone face to face with hostile or argumentative intent") someone when you want their assistance usually leads to a "thanks, we'll get back to you, there's the door don't let it hit you on the way out" response. And going to the "coming out party with a nice bag of poo" will no doubt be equally as off putting.
But hey, that's just me. I was told you catch more flies with honey than vinegar. I can understand your frustration but you may want to consider another approach. In any case good luck.

Black&White

Exactly, face to face in a room full of potential buyers and the Corvette / automotive press. now you got it.

Woodson

You'll come off as a lunatic.

DBLXX

Kind of like how Black Lives Matter confronted Trump recently?



Face to face in a room? Sorry - ain't happening.

Black&White

He was/is part of the team that over sees the whole platform? Let's not forget they were selling and making cars with them knowing the transmissions were defective and going to be discontinued and secretly designing a new version with a new part number the whole time. Bottom line is they knowingly produced and sold cars with defective transmissions and failed to disclose it.

Not with the Lawyers in tow I won't. See post #6 This is no fly by night operation I just want to help anyone else out since I have done most of the leg work already. I have had 5 A8s sent to an independent lab and torn apart ( and not all from C7s) and you will be surprised of the findings when we are finished. Hint...you won't be happy if you own one.

cg02175

Don't let some of these guys discourage you from voicing your concerns. Countless people have had issue with their A8 (i.e hard downshifts, overheating, and more), so this needs to be brought forth.