Another A8 Thread
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Le Mans Master
Joined: Sep 2006
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From: Palm Harbor not far from Sebring Florida
St. Jude Donor '11
Oldtimer
Another A8 Thread
Ok, so we all are well aware of the A8 Trans shutter and the service bulletin on the triple flush. If it is not done and a driver continues to drive and put up with the shutter, will it end up taking out the torque converter ort possibly the torque tube?
Next question is if you drive the car in the manual mode the shutter is not an issue, so why is that?
So, could this shutter issue actually be a part of the computer dropping the 4 cylinders and the issue with the trans fluid.
Next question is if you drive the car in the manual mode the shutter is not an issue, so why is that?
So, could this shutter issue actually be a part of the computer dropping the 4 cylinders and the issue with the trans fluid.
Team Owner
Joined: Jul 2004
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From: Hartford WI
I would think that you should be able to drive in any mode you wish and it should not SHUDDER not shutter. To me, driving in paddle mode to avoid shudder is like taking pain meds so you feel no pain from the broken leg without fixing it. It seems to me, never had it before, is that the dropping in and out of V4 to V8 shows the fault but look at it this way. If you cannot see a problem, does it mean the problem goes away? I think not. If the fluid is bad because it is hygroscopic and the A8 is more susceptible to water in the fluid why wait till it has a problem? If you accept that the fluid is not right, I would change it BEFORE the problem comes along which means that the fluid with water has been going around till the symptom appears. If your tire is leaking, do you keep it pumped up to avoid running flat or do you fix the problem so you don't get it running flat? Just comparing a similar situation.
Melting Slicks
Joined: Sep 2011
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From: Vancouver Island
I believe the shudder is due to too much slippage in the lock-up clutch in the TC. If you don’t do the flush, likely the lock up clutch will become glazed and the TC will need to be replaced.
V4 mode does not activate when you are in manual shifting mode. I think the harmonics or vibrations of v-4 mode contribute to excess slippage. The TC has to unlock and then re-lock every time the engine goes in and out of v4
Just my .02 based on what I’ve read.
Bottom line, to enjoy the car properly and not risk damage, get the flush done sooner rather than later.
V4 mode does not activate when you are in manual shifting mode. I think the harmonics or vibrations of v-4 mode contribute to excess slippage. The TC has to unlock and then re-lock every time the engine goes in and out of v4
Just my .02 based on what I’ve read.
Bottom line, to enjoy the car properly and not risk damage, get the flush done sooner rather than later.
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^ I agree - get the flush done and then consider getting the Range AFM Eliminator - keeps the engine from going into V4 mode.
Melting Slicks
Joined: Sep 2011
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From: Vancouver Island
Also, as posted above the original fluid is hygroscopic and more susceptible to getting water in the fluid. Water will damage the friction surface of the clutch. V4 mode may or may not be the cause of the problem (who really knows for sure), but it will compound it. Point being, the original fluid can still wreck the transmission even if you never engage v4.
Le Mans Master
Joined: Oct 2014
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From: Atlanta GA
Also, as posted above the original fluid is hygroscopic and more susceptible to getting water in the fluid. Water will damage the friction surface of the clutch. V4 mode may or may not be the cause of the problem (who really knows for sure), but it will compound it. Point being, the original fluid can still wreck the transmission even if you never engage v4.
The lockup converter is never really locked up totally , it is pulsed . The converter is pulsed differently in 4 cylinder mode and 8 . Driving in manual mode the TCM does not command TC lockup
Dave
