[20v] Rear drive shaft excessive movement

[Bernie Benz]

I’ll second that John! 

I DIY realigned one many, many  years ago on a ‘88 5k.
I gilded the lily on that one by first aligning the tranny output shaft with the rear end input shaft. Not a factory alignment.
 
To make the axes of these two shafts congruent, i.e. their axes on the same straight line, I had to rotate the engine on its subframe around its vertical axis and raise the back mount of the rear end. The simple tooling for this exercise is a piece to string stretched tight between the OD of the two (same diameter) flanges and a 12” machinist’s square. The string must be perpendicular to the face of each flange in each of two mutually perpendicular planes for the shafts to be congruent.

The center bearing must be shimmed such that the axes of the half shafts are also congruent. Inasmuch as the two shafts are of the same diameter, their outer surfaces can be made congruent in each of two mutually perpendicular planes and the shafts will be congruent. These mutually perpendicular planes need not be horizontal and vertical. To clear immovable obstacles they are 45 degrees down, left and right. The simple tooling for this is a 4’ or 5’ straight edge with a cut out to clear the center bearing and U joint.

More than you ever wanted to know? But it was the smoothest running drive train that I’ve ever not felt!

Now that I’ve gone to this write up trouble, I’ll post it as a Tech Article on both the AW and QW forums, where I reside as the forums‘ contrarian contributor.

Bernie
Gardnerville, NV
'90 90Q-20V175K grandson’s 
'91 200Q-20V 235K
‘02 A6 2.7TQ 6spdMT 135K
'88 FordQuatroTractor
Other Misc. Toys





On Jul 26, 2012, at 3:31 PM, john at westcoastgarage.net wrote:

>> http://www.034motorsport.com/chassis-components-audi-40008090urq-audi-4kq8090coupe-driveshaft-support-bearing-p-351.html
>> 
>> 
>> ---- Wylie Bean <theringmeister at triad.rr.com> wrote:
>>> 034motorsport.com
>>> .... no experience with it personally tho
>>> 
>>> 
> Keep in mind that buying the bearing and mount assembly is the first, and
> by far the easiest, step in the process.  It gets exponentially harder
> from there.
> 
> John
> 
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