Replacing Front Left or Right Spring-Strut Shock Absorber
Replacing Front Left or Right Spring-Strut Shock Absorber
Whether a spring strut shock absorber unit has to be replaced can only be determined by testing while it is installed with a shock tester or while it is removed with a shock absorber test machine.
When a spring strut shock absorber is replaced, a spring strut shock absorber with the same identification marking (K) must be installed.
1=BMW number
2=Suspension design:
4Z Series=4-cylinder Series
6Z Series=6-cylinder Series
4Z Sport=4-cylinder sports suspension, low-slung
6Z Sport=6-cylinder sports suspension, low-slung
3=Side designation:
L=left/R=right
Remove front wheel.
Detach cable and brake hose from mounting.
Remove brake caliper and tie back to body.
Car with headlight range adjustment:
Remove retaining bracket (1) of angle joint from control arm (2).
Release nut-grip with open-end wrench-and detach stabilizer link.
Installation:
Replace self-locking nut.
Tightening torque, refer to specification.
Release nut and press steering tie rod off steering knuckle with special tool 32 3 090.
Installation:
Replace self-locking nut.
Tightening torque 65 Nm
Release nut, force control arm off steering knuckle with special tool 32 3 090 and detach.
Installation:
Replace self-locking nut.
Tie rod end nut 36.5 ±3.5 Nm
Note: Tie rod end with split-pin hole must not be bolted with a self locking nut.
Secure steering knuckle against falling off.
Unscrew multipurpose bolt a few turns.
If necessary, spread out steering knuckle with special tool 31 2 200 and remove towards bottom.
Installation:
Insert positioning pin (1) into gap and press steering knuckle upwards onto stop.
Control arm on steering knuckle/swivel bearing 80 Nm
If there is no centering pin (1) or bore (2), only one nut may be released.
The centering pin is screwed into place on the M3 model.
Position of threaded pin to wheel arch must be precisely marked. This ensures that the original camber is retained during installation.
Remove support bearing from wheel arch.
Installation:
Replace self-locking nuts. The centering pin (1) of the support bearing must lie in the bore (2) of the wheel arch, and the marking must be noted.
Clamp special tool 31 3 341 at guide (1) in vise.
Slide in special tools 31 3 354 and 31 3 355 in each case from chamfer of special tool 31 3 34. Locking pins (2) must be felt and heard snapping into place.
M3 model only: Clamp special tool 31 3 341 at guide (1) in vise. Slide in special tools 31 3 352 in each case from chamfer of special tool 31 3 341. Locking pins (2) must be felt and heard snapping into place.
Warning!
Before they are used, always check that the special tools work properly.
Do not use damaged tools.
Do not make any modifications whatsoever to special tools.
Use only suitable spring retainers.
The special tool 31 3 341 is designed exclusively for tensioning and releasing chassis springs; never use an impact screwdriver for tensioning/releasing purposes.
Keep protective inserts clean and free from oil and grease.
You will be exposed to an increased risk of injury if you fail to comply with the above-mentioned points!
Spring retainers must each be inserted from chamfer (1) of special tool 31 3 341. Locking pins must be felt and heard snapping into place.
Check seating of spring retainers again.
Position protective insert 31 3 101 on spring plate.
Accommodate coil spring between spring holders.
End of spring (1) must be flush with end of spring holder (2).
When tensioned in the spring holder, the spring coil must rest completely in the recess.
M3 model only:
Accommodate coil spring between both spring holders (special tool 31 3 352).
End of spring (1) must be flush with end of spring holder (2).
When tensioned in the spring holder, the spring coil must rest completely in the recess.
Warning!
When tensioned in the spring holder, the spring coil must rest completely in the recess.
The special tool 31 3 341 must not be tightened or untightened with an impact screwdriver.
The coils may not be tensioned on a block.
Only tighten down the coil springs until stress on the thrust bearing is relieved.
The nut may only be released when the spring coil is resting completely in the recess of the spring holder! Repeat tensioning process if necessary.
Release nut with special tool 31 2 210-grip piston rod firmly if necessary-and remove spring strut shock absorber.
Follow Notes 1...3 if a new coil spring is installed.
Note 1:
Release special tool 31 3 341 and remove coil spring. The special tool must not be tightened or untightened with an impact screwdriver.
Note 2:
Check spring pad (1), replace if necessary.
Fit spring pad (1), spring plate (2) and protective insert 31 3 356 onto new coil spring.
Make sure that end of spring, spring pad (1) and spring plate (2) form a positive connection.
Note 3:
Place coil spring in spring holders. End of spring (1) must be flush with end of spring holder (2).
M3 model only:
Refer to Note 3.
Warning!
When tensioned in the spring holder, the spring coil must rest completely in the recess.
The special tool must not be tightened or untightened with an impact screwdriver.
Tension coil spring.
The coils may not be tensioned on a block.
Replace auxiliary spring (1) if necessary.
Check protective tube (2) and spring pad (3), replace if necessary. Opening on spring plate and spring pad must be flush.
Installation:
M3 model only
End of spring (1) must not touch against shoulder of spring pad.
The recess (2) only serves to reinforce and correctly seat the spring pad and does not serve as a stop for the spring end.
Spring pad must form a positive connection as it rests in coil spring.
Insert spring strut shock absorber into coil spring and upper spring plate.
Observe installation sequence, refer to Arrangement for spring strut shock absorber.
Replace self-locking nut (1) and screw onto piston rod so that it is flush.
Coil spring must fit positively in lower spring plate/spring pad.
Release tension on coil spring until it is fully resting in lower spring plate.
Tighten self-locking nut with special tool 31 2 210.
If necessary, grip piston rod. Tightening torque, refer to specification.
Fully release tension on coil spring and remove.