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Evil is as Evil does
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I took my car into the dealer to have new tries mounted, oil change and such. I also asked them to check out a noise that sounded like sharp clank sound when getting off the clutch pedal. Very easily noticable in first and second gear. If I am gentle with the clutch pedal I can keep it from happening. The dealer tells me there is no TSB, but there is a PI open for it. On the workorder they documented this as PIP 3896 and say that the noise is normal. Does someone here have access to the full contents of that PI and can post it here? I know there's a lot of threads about drivetrain noise but none that mention this PI.
 

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Got MPG? Yes, it's a diesel.
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I actually get this noise every once in a while, but it also happens in reverse sometimes.
 

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......................... ....
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The dealer is right for once it's normal. They all do that, I don't like it but I can't complain because it's been making that noise for 2 years and 28k miles now and still running fine.
 

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gotta love a gto
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it is considered normal operation. torque reversal it is called. caused by all of the drivetrain lash.
 

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EvilTwin said:
I took my car into the dealer to have new tries mounted, oil change and such. I also asked them to check out a noise that sounded like sharp clank sound when getting off the clutch pedal. Very easily noticable in first and second gear. If I am gentle with the clutch pedal I can keep it from happening. The dealer tells me there is no TSB, but there is a PI open for it. On the workorder they documented this as PIP 3896 and say that the noise is normal. Does someone here have access to the full contents of that PI and can post it here? I know there's a lot of threads about drivetrain noise but none that mention this PI.
Subject: Clunk Noise When Shifting More Noticeable at Low Speeds - keywords clutch manual throttle transmission #PIP3896 - (08/21/2006)



Models: 2004-2007 Cadillac CTS-V

1997-2007 Chevrolet Corvette

2005-2006 Chevrolet SSR

2004-2006 Pontiac GTO

Equipped with a Tremec 6-speed Manual Transmission




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

Condition/Concern:
While driving in a steady slow speed parade type situation a clunk-clunk noise from the driveline may be heard when depressing and releasing the clutch pedal, between shifts or quickly depressing and releasing the throttle.

Recommendation/Instructions:
The noise is a normal torque reversal in the driveline and a combination of axle backlash, front and rear drive shaft rubber isolation flanges, drive shaft center support, and a dual mass flywheel all working together. This is a normal characteristic and not a condition of operation concern. No repairs should be attempted.

Also reference the latest version of TSB 03-07-29-004 for further manual transmission operating characteristics.

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
 

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I'm glad someone posted this as mine too has this condition... a part of me figured it was 'normal', but I still consider it unacceptable. I’ve been driving manuals continuously for 20+ years… my manual 5-series didn't do this, nor have any of several manual Benzes I've driven (or at least to a degree where I noticed it)... proving it can be engineered out of a RWD system. It's apparent the cause is too much total lash (slop) in the drivetrain between the flywheel and pavement. Didn't know the technical term (torque reversal) but learned from the outset the only way to avoid it was unloading the drivetrain as much as possible during clutch engagement/disengagement. A big part of it is pressing and releasing the pedal a little more slowly than is natural so the forces in the driveline are slowly released or taken up. Actually had to change my shifting technique some to compensate for/avoid it. Another point is that the car be neither noticeably accelerating nor decelerating before pressing the clutch pedal... just maintaining current speed or slightly coasting down. Easing up on the gas just a bit before shifting; slowly and fully pressing the pedal, adjusting throttle, shifting and getting the RPMs to where they are going to be in the next gear, and finally slowly releasing the pedal while slowly adjusting the throttle so that crank and tranny input speeds are the same by the time the pedal is all the way up is the only way I can avoid the noise. Basically the Driver's Ed/textbook version of driving a stick. Any deviation from this and I hear the clank; sometimes on the spin down and others on the spin up... depends on where I went wrong. I also believe my car might be more affected than average too (or maybe its driver, who knows)... it’s way too unforgiving in my opinion. The plus side I suppose is after a year of this training my shifting smoothness has gotten to the point (through necessity) where a passenger with me couldn’t tell if they were in a conventional auto or stick by feel alone. I’m still working on getting as smooth as the CVT in my Dad’s Murano – NOT. :)
 

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CLTGTO: It's not a Beemer or a Benz...It's a friggin Pontiac. Have you noticed all the rubber bands in the driveline???? Drive it like you stole it and don't worry about the clunking and clanging.

2QWK4RU 06 GOAT: Enough the the caps already. We all realize how important you are to yourself. You don't need to shout all the time!!!!!
 

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I'm gonna get you!
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Phantomblack06 said:
CLTGTO: It's not a Beemer or a Benz...It's a friggin Pontiac. Have you noticed all the rubber bands in the driveline???? Drive it like you stole it and don't worry about the clunking and clanging.

2QWK4RU 06 GOAT: Enough the the caps already. We all realize how important you are to yourself. You don't need to shout all the time!!!!!

I've dirven an m3 and it does it as well. Backlash is normal in all gear system.
 

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Moderhatin'
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I took mine into the shop cause i was hearing a clank whenever i got out of gear. The dealer told me that it was coming from the drive shaft when it came out of loaded condiditons. The drive shaft is under torque and when it releases the joints tend to rattle together. This is a completely normal thing. The only way to get rid of it is to either grandma drive your car or get a A4.
 

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Phantomblack06, point taken... and I occasionally do emulate an auto theft... but it's still annoying when I'm just loafing around.
 

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I've found that if you stay on the gas a hair longer when pushing in the clutch you'll almost always eliminate the "clank". So used to doing it this way its become natural.
 
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