Drive shaft, remove and install.

Remove exhaust system

Remove heat shield from above exhaust. Secured by two 10mm screws at the rear (yellow arrows) and a total of twelve 13mm bolts ( green arrows) including the 6 securing the cross brace just behind the transmission.
Remove the three 17mm nuts and bolts securing the "Guibo" coupling to the transmission. Leave the Guibo attached to the driveshaft.
Loosen threaded ring at center support. This is best achieved with two large pairs of pliers, apply one set of pliers to the threaded ring (green arrow) and the second set to the weld in the driveshaft tube (yellow arrow). The weld is a rough surface and gives good grip, preventing the pliers from slipping and scarring the tube. It is also the strongest section of the tube. Loosen ring approximately 5 turns.
Remove the four 17mm nuts securing the rear driveshaft flange to the differential input flange. Prevent the drive shaft from turning by either holding with pliers at the rear weld on the tube, placing the trans in gear, or engaging the parking brake. Remove bolts from center support, push driveshaft rearwards to collapse slip joint at threaded ring, pull center of driveshaft down and forward end will come off transmission.
Remove bolts from center support, push driveshaft rearwards to collapse slip joint at threaded ring, pull center of driveshaft down and forward end will come off transmission.
CAUTION : Do not allow driveshaft to contact fuel transfer pipe between fuel tank halves.
CAUTION : Drive shaft is balanced as a unit, do not separate the two halves without marking them for correct re-assembly.

Installation

Check center bushing on transmission end of shaft, replace if necessary, lubricate bushing with grease.
If Guibo has been removed from driveshaft, ensure that arrows on Guibo point to a flange. White arrows show position of arrows on Guibo. Green arrows show orientation of those arrows. Each arrow is pointing towards either the transmission output flange, or the driveshaft flange.
Pre-load center support by moving forward 4 - 6mm from it's relaxed position, before tightening. Ensure bracket is straight before tightening.

Replace gasket and nuts at exhaust manifold flange. Use copper nuts.
Install manifold nuts and muffler straps and tighten to correct torque before installing other mounts.
Muffler straps must be preloaded. Install the straps so that the rubber hanger is pulled 6mm forward with a cold exhaust.
Correctly positioned exhaust must have tailpipes in center of opening in rear valance.
Install rubber hanger and bracket at rear sub-frame and position bracket so that rubber hanger has slight tension only.

Torques
Center support	:	22 Nm (16 ft lbs.)
Guibo	:	10mm 8.8 bolts, 46 Nm (33 ft lbs.) ; 10mm 10.9 bolts, 72 Nm (52 ft lbs.) ; 12mm bolts, 123 Nm (89 ft lbs.)
Rear flange to differential	:	72 Nm (52 ft lbs.)
Threaded sleeve	:	17 Nm (12 ft lbs.)
Pipe to manifold	:	Step 1, 30 Nm (22 ft lbs.) Step 2, 50 Nm (26 ft lbs.)
Muffler brackets	:	M10, 16 Nm ( 11 ft lbs.). All others, 14 Nm ( 10 ft lbs.)
Hanger bracket to rear sub-frame	:	22 Nm (16 ft lbs.)

E30 M3 Repair Manual V2.7. Copyright Š1999-2001 Koala Motorsport & Brett Anderson