When replacing torque tube in '87 S4 (automatic) is it necessary to re-set rear suspension?

 

Mark the adjusters before removing them and re-set it that way. You'll likrly only remove the front, toe adjusters.

 

Just remove the whole suspension subframe as one unit. Much easier that way.

 

If by 're-set' you mean do a 4-wheel alignment then, as GlenL wrote, if you mark the toe eccentrics(*) before you remove them and then get them back in the same spot, changes to alignment will be minimal at worst.

(*) Make sure you mark them "L" and "R" in addition to marking the orientation on the eccentric and the chassis. That way if you get them mixed up...

 

My memory must be failing faster than I realized. Why would you remove the any of the eccentrics to replace the torque tube? You drop the suspension as a unit without touching the eccentrics. You just need to mark the position of the crossmember outer mounts.

For that matter, you really don't need to remove the rear suspension at all to replace the TT. After you expose the TT, loosen the TT front clamp. Remove the the front flexplate from the flywheel, slide it back a bit. Remove the front bolts on the TT to bellhousing. Pop the kickdown cable off the throttle quadrant. Remove the band clamps on the TT that retain the kickdown cable and tranny fluid lines. Remove the shift cable and its bracket from the tranny. Remove the lower tyranny mount bolt to the crossmember and slide the tranny and TT back. You can create a bit more room by unfastening the parking brake cable from the crossmember and pulling it down out of the way. Remove the bellhousing, unfastening the kickdown bracket on it. Loosen and remove the rear TT shaft clamp bolt. Tilt the front of the TT down until it clears the flywheel. Using a long ratchet/breaker bar, undo the rear TT bolts to the torque converter. They can be tough at 88 ft lb. For the upper bolts use ~3 feet of 1/2" extension. Pull the TT out of the torque converter. Reverse to put in new TT. That's how I have done it several times. No need to drain the tranny, etc.

It's quite similar to my method for replacing the engine's rear main seal without removing the tranny and rear suspension, with some additional steps needed to remove the TT.
http://www.billsworkshop.com/P928S4/seal/seal.htm

I'd be happy to drop by and help with the TT job. I've done it alone, but it is considerably easier with some extra hands.

Funny anecdote: I thought at 200K miles, my TT MUST need new bearings. So, I did the above to remove the TT. I planned to remove and replace the bearings. I got a length of ~3" PVC pipe to shove down inside the TT to pound out the bearings with my 5lb sledge. I beat the living crap out of the pipe and the bearing carriers would not budge a millimeter. I wiggled and spun the TT shaft. It was firm with no discernable play and the shaft did not freewheel or rattle. I gave up and put the TT back in further unmolested. The original TT bearings are still in there today at 282K miles.

 

Because California.