A4 vibration and noise
Thread Starter
Melting Slicks
Joined: Jun 2003
Posts: 2,170
Likes: 48
From: Yuma CO
Senior Member
Cruise-In V Veteran
A4 vibration and noise
Just picked up my second A4 '99 coupe and love it, but on the way home (600 miles) in the mountain passes just outside of Salt Lake City, I was climbing the passes. With the cruise set, it had to drop 2 gears for the cruise control to try to maintain speed. When it did this there was a severe vibration and noise until the tranny upshifted. I think it is probably my imagination, but the second time this happend, I thought I smelled a hot oil/lubricant smell (might have been my panic). I think, but am not sure at this point, that if it drops one gear, everything is fine. If it drops two gears, the vibration and noise happens. The same thing happened when I was operating the throttle, so it is not a cruise-only occurance.
Other than the occurance, there is absolutely no vibration, noise, whine, or any reason to suspect that anything is amiss. It is only when the tranny downshifts dramatically that it occurs, and with road noise, my elderly hearing loss, and wind noise, it is a little hard to have a solid idea of the real symtoms.
Has anyone else experienced this problem?
Other than the occurance, there is absolutely no vibration, noise, whine, or any reason to suspect that anything is amiss. It is only when the tranny downshifts dramatically that it occurs, and with road noise, my elderly hearing loss, and wind noise, it is a little hard to have a solid idea of the real symtoms.
Has anyone else experienced this problem?
Instructor
Joined: Dec 2006
Posts: 115
Likes: 0
From: Metro Detroit
What was the rpm that was reached after the second downshift?
Can you reproduce the vibration by hitting that same rpm with a normal WOT acceleration out of 1st or 2nd gear?
Did you check if you have any wet oily spots on the transmission or the oil cooler in the radiator that might have caused the burned smell at WOT?
The trans pressure is the highest in the case of WOT, maybe you spray some oil out from somewhere under these conditions.
Can you reproduce the vibration by hitting that same rpm with a normal WOT acceleration out of 1st or 2nd gear?
Did you check if you have any wet oily spots on the transmission or the oil cooler in the radiator that might have caused the burned smell at WOT?
The trans pressure is the highest in the case of WOT, maybe you spray some oil out from somewhere under these conditions.
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 328
From: CA.
St. Jude Donor '13-'14-'15
Cruise control while climling is the mountains ??? NO NO--asking for trouble--On a typical car that shifts at 4500 no big deal--but on a sports car that shifts at 6000 letting the ECM control the up/dwn shifts leaves too much room for error and ignores common sense--You bought a sports car---DRIVE IT----
Pro
Joined: Aug 2010
Posts: 593
Likes: 9
From: San Antonio Texas
It is hard to say given your description of the symtoms but I would imagine that you were maxing out the torque converter at low RPM and high demand. I think it would be equal to lugging an engine in high gear going up a steep hill. You didn't do your car any favors by engaging the cruise control and climbing a long steep grade. Did you check the fluid level the way the owner's manual instructs? It doesn't sound like you have done any short term damage. The A4 is a very robust transmission and I doubt you did anything that the original design engineers didn't do to it when it was tested! Good Luck.
Tech Contributor
Joined: May 2008
Posts: 3,100
Likes: 17
From: Somers, CT and Clermont, FL
St. Jude Donor '09-'10-'11-'12-'13-'14-'15-'16
The owner's manual does not have the printed instructions needed to check the fluid level. It can only be found in the factory service manuals, and also in my sticky post located at the top of C5 Tech section.
