Replacing Front Left or Right Spring-Strut Shock Absorber

Replacing Front Left or Right Spring-Strut Shock Absorber


Whether a spring strut shock absorber has to be replaced can only be ascertained by checking while it is installed with a shock tester or while it is removed with a shock absorber test machine, refer to specification Shock absorbers.





When replacing the shock-absorber element for a McPherson strut, always ensure that the replacement unit is marked with the same code (K) as the old absorber.
1=BMW number
2=Suspension design:
4Z Series=4-cylinder series
6Z Series=6-cylinder series
4Z Sport=4-cylinder low-slung sports suspension
6Z Sport=6-cylinder low-slung sports suspension
3=Side designation:
L=left/R=right





Remove front wheel, refer to 36 10 300.
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 65 Nm





Release nut, force tie rod with special tool 32 3 090 off steering knuckle.

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.
Release multipurpose bolt.
If necessary, spread out steering knuckle with special tool 31 2 200 and remove towards bottom.
Tie back steering knuckle.

Installation:





Insert positioning pin (1) into gap and press steering knuckle upwards onto stop.
Tie rod clamping screw 14 Nm
Note: Tighten in empty weight or in normal position.





If there is no centering pin (1) or bore (2), only one nut may be released.
Position of threaded pin to wheel arch must be marked exactly. 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.
Spring strut mount to wheel house
Flanged hexagon nut 18 mm 24 Nm
Flanged hexagon nut 21 Nm 34 Nm






Clamp special tool 31 3 341 at guide (1) in vise. Locking pins must be felt and heard snapping into place.

Warning!
Prior to each use, check special tools for functional capability.
Do not use damaged tools.
Do not make any modifications to special tools.
Use only suitable spring retainers.
The special tool 31 3 341 is designed exclusively for tightening and untightening springs; never use an impact driver for tightening/untightening.
Special tools 31 3 355 and 31 3 354 must be kept absolutely dry and free from grease!





Spring retainers must be pushed in from chamfer side (1) of special tool 31 3 341.
Locking pins must be felt and heard snapping into place.
Check seating of spring retainers 31 3 354/31 3 355 again.





Position protective insert 31 3 356 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.

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.
If a new coil spring is installed, follow Notes 1...3.

Note 1:
Relieve tension on 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 on 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).

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.





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 form a positive connection as it rests 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. Fully release tension on coil spring and remove.