From: CAPTEARLG@aol.com
Sent: Friday, October 13, 2000 10:06 AM
To: 928
Subject: [928] Torque Tube BIGGYs

"Tony H" says,
OK guys...
When i get home and over the next week im going to be dropping the TT.

What are the big items to look for. Im looking along the lines of Thrust 
bearing failure.
example
....undoing the collar bolt on the drive line ...the drive shaft should or 
shouldnt slide....which direction????

....something about retorquing this collar bolt to a HIGHER torque setting 
to prevent movement and prelaoding the shaft during installation...doing 
this when the car is HOT or COLD?

....preload..clearence...crankshaft play etc etc

....flexplate condition, what am i looking for.

I know these items have been covered over NUMEROUS VARIOUS posts  in the 
past and may take some detail to explain but to make it easier for me 
perhaps the people in the know could sumerize.
Taking it all apart is easy...its KNOWING WHAT TO LOOK FOR  AND WHAT 
POTENTIAL PROBLEMS I MAY HAVE HIDDEN FROM ME THAT IS THE CONCERN !

Tony,

Drop the exhaust. 
Remove the bell housing bottom cover.
Install a dial indicator on the rear side of the forward Drive Shaft Hub.
Loosen The hub clamping screw.
On the three automatics that I have done this on, the hub moved back between 
.100"and .120". This preload puts pressure on the rear face of the crankshaft 
thrust bearing. If the hub does not move more than a few thousandths of an 
inch when you loosen the pinch bolt then all is OK.

After the pinch bolt is loose then put the dial indicator on the flywheel, 
(not the flexplate). Pry the flywheel back and forth to check the crankshaft 
end play. The spec for later engines is .0024" to .0076". Wear limit is .016".

If your end play is more than .016", then you are experiencing "Thrust 
Bearing Failure".

When you install your TT, tighten the forward hub pinch bolt last. Tighten to 
110% of factory spec. 66ft lb. It doesn't matter if you tighten hot or cold 
or the position of the crankshaft.

We tried loctite on the shaft and bolt of one car to see if we could stop it 
from sliding forward on the shaft, but we have not checked to see if it has 
worked. We will check in a few weeks and post the results.

Earl Gillstrom 88 S4 5 Speed 
Crankshaft end play .007" at 91,000 miles