Re: Transmission noise

["Dahl, Dave" <dad@roadnet.ups.com>]

     I would suggest these steps:
     
     1.  Check the level of the trans lube.
     
     2.  You could try fresh lube.  I had a trans noise in neutral for a 
     long time, and it went away when I put fresh synthetic oil in the 
     trans and center diff.  When you drain the center diff, check the 
     magnetic drain plug for signs of self-destruction.
     
     3.  Live with it until it becomes obnoxious.  I've had a noisy rear 
     diff in my Syncro for years.  It has finally gotten to the point where 
     it gets extra loud once or twice for a short time in cold weather.  
     I'm still in no hurry, since I can't find a used rear diff anyway.  
     I'm sure it will last at least a couple more years, since it mostly 
     just emits a low hum now.
     
     4.  Give the other car snow tires and 2 bags of cement.  :)
     
     The mechanic's advice to wait until the noise is louder is probably 
     good.  It's difficult to diagnose this type of problem before then.  
     You can usually go quite a while before anything serious will happen.
     
     - Dave Dahl  (dad@roadnet.ups.com)
     - '87 VW Quantum Syncro
     - '93 Volvo 850 GLT
     

______________________________ Reply Separator _________________________________
I have an Audi 5000CS Quattro, and had the front struts replaced last 
fall.  It then started making more "road noise" than it did before, 
but my mechanic does not know if it is really road noise or not.
A friend and I jacked up the car and ran it with all wheels off the 
ground, and it made noise from the transmission/front diffs.  When 
we turned the right front wheel by hand, the left front wheel turned 
in the opposite direction, and there was no noise.  However, when
we turned both front wheels the same way at the same time, there 
was noise from the transmission/front diffs.
     
Last Thursday, it seemed to howl a little at low speeds.
     
My mechanic claims that if you take the wheels of any 4-wheel drive 
car off the ground, it will make noise because the weight makes the 
bearings tight.  He does not hear anything unusual, and says it will 
cost over $250 just to pull the transmission and send it somewhere
where they can take a look.  He says that he would just run it until it 
makes a lot more noise and then can pinpoint where the problem really 
is.  I am thinking of doing this, as I need the AWD for the winter,
and my other car is RWD.
     
Any comments or suggestions?
     
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