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Replace rear control arm or bushing

Remove appropriate wheel.
Left side, remove exhaust
Remove the six 8mm Allen head bolts and 3 supports (blue arrow) securing each axle to the differential.
330004.jpg (15347 bytes)
Axle can be removed from control arm or tied to control arm in such a way as to alleviate any undue stress on outer CV joint.
Right side, disconnect brake lining light sensor.
If control arm is being replaced, break loose flexible line at caliper with a 14mm flare nut wrench while caliper is still bolted to control arm.

If only control arm bushings are being replaced, there is no need to open this line other than to remove some weight from the control arm while working on it.

Remove both 17mm bolts securing brake caliper bracket to control arm. There is no need to remove the caliper from it's bracket. 340010.jpg (58367 bytes)
CAUTION: Do not allow caliper to hang from flexible hose.
Pull caliper towards outside of car to force pads apart and slide caliper off rotor.  If caliper is to be left with control arm, tie caliper up temporarily. 340012.jpg (55756 bytes)
If caliper is to be removed, unscrew it from the flexible line and place aside.
Remove 5mm Allen bolt securing rotor to hub. If bolt head is stripped, and rotors are being replaced, use a hammer on the back of the rotor to break it off the hub. This will allow you to get full access to the head of the bolt with a pair of vice grips or even to cut a slot in the head for a screwdriver. 340014.jpg (18657 bytes)
The only purpose of this bolt is to retain the rotor while installing the wheel, if necessary, it can be left out, although it may cause problems later if you have to change a tire on the side of the road.
Remove rotor, if rotor is stuck to hub , hit it with a hammer. If rotor is to be re-used, do not hit the outer surfaces, hit the rotor where the wheel bolts go through. The shock of a few good hits will bounce the rotor off the hub, be careful not to drop the rotor.
Wind adjuster (red arrow) in to minimum setting. Remove both springs (green arrows). Insert 5mm Allen key into shoe retainers and twist 90°. Release pressure on retainer and remove. Do not drop shoes. Place shoes aside. 340015.jpg (18806 bytes)

Note : Hub has been removed for clarity of photographs.  Do not remove hub unless you intend to replace wheel bearing.

Pull lever forward to expose cable pin. 340016.jpg (13873 bytes)
Slide pin (arrow) out of cable end and push cable through backing plate. 340017.jpg (11874 bytes)
If caliper was not removed from flexible line earlier, bolt it back onto the control arm to prevent it dropping during removal of the control arm.
Loosen the 17mm nut and bolt on each leg of the control arm, do not remove them yet.
Support control arm and remove lower shock absorber mounting bolt. 330026.jpg (15913 bytes)
Remove 13mm nut from sway bar link and disconnect link from control arm 330027.jpg (15988 bytes)
Gently lower control arm as far as it will go.  Pull down on top of spring and out towards the side of the car to remove. 330028.jpg (17411 bytes)
Place support back under control arm and remove 17mm nut and bolt from each leg of the control arm.

CAUTION: Control arm is heavy, be prepared to take the weight when shock mount is released

Pull control arm out of sub-frame and remove from car.
Press control arm bushings from the inside out.

Installation

Lubricate new  bushings with soapy water or some other evaporating lubricant.
Press in new bushings  with collar end facing out.
Install control arm bolts, without tightening, before tightening sub-frame mount nuts.  The extra play in having the sub-frame loose will make control arm installation easier.
Do not tighten control arm bolts until everything else is assembled.   Place vehicle's weight on its wheels to correctly pre-tension the bushings before tightening control arms.
Vehicle's rear wheels can be placed on blocks or spare wheels to achieve pre-loading while still allowing access under the rear of the vehicle to tighten the bolts.
Bleed brake system

Torques :

Control arm to sub-frame (suspension loaded) : 67 Nm (48 ft lbs.)
Sway bar link to control arm : 21.5 Nm (16 ft lbs.)
 

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E30 M3 Repair Manual V2.7.  Copyright ©1999-2001 Koala Motorsport & Brett Anderson