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I Steerina and Wheel Alianment
Steering
system
Two types of steering gear are used in the E39 series models.
6-cylinder
(5251, 528i and 530i) models are equipped with
rack and pinion steering. The steering rack is mounted to
an aluminum subframe.
V-8
(540i) models are equipped with a recirculating ball
and nut steering gearbox mounted to a steel subframe.
At low speeds, maximum power assist is provided to ease
parking and city driving. At high speeds, assist is reduced to
ensure stability. The power steering system varies assist
based on engine speed.
Power boost for the steering is provided by an engine-driven
hydraulic pump. A hydraulic control valve is used to control
boost pressure.
The steering wheel connects to the steering gear via an ad-
justable steering column which incorporates a rubber cou-
pling ("guibo") to dampen vibration and noise.
Power steering fluid is supplied from the fluid
reservoir to the
pump and to the steering gear via rubberlmetal hoses.
The return line from the steering gear to the
reservoir loops
into the airstream in front of the radiator and connects to the
steering fluid cooler. The fluid cooler is attached to a cassette
which also includes cooling coils for engine oil, transmission
fluid and AIC condenser.
The steering gear requires no maintenance other than align-
ment and periodic inspection for worn components. Inspect
rubber rack boots
(rack and pinion system) and tie-rod end
boots periodically for tears or damage. Replace
if necessary.
-
NOTE-
The airbag system is traditionally referred to as Supplemen-
tal Restraint System (SRS). The
BMW versfon of SRS used
m the E39 models is known as the Multiple Restraint System - (MRS). - -
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Steering and Wheel Alignment
I Rack and r in ion steering 1 Steering system variations
I 6-~~linder'rnodels (525i,>28i, 530i) / 1. Left tie rod
2. Right tie rod
3. Steering rack
4. Steering gearbox
5. idler arm
6. Center tie rod
7. Steering knuckle
Recirculating ball and nut steering
r V-8 models 154Oib
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Steering and Wheel Alignment
4 Release lock (A) and pull up on harness connector (6) to dis-
connect ignition switch harness.
. Remove wire harness bracket fastener (C).
4 Remove shear bolts (arrows) using a chisel or punch.
NOTE-
The shear bolts can be drilled and then removed using an
easy-out.
- Remove steering column lock housing.
- Installation is reverse of removal.
Tighten new shear bolts until bolt heads shear off.
ignition interlock cable, removing and
installing (models
with automatic
transmission)
- Remove steering column trim panels as described earlier.
4 Loosen and disconnect interlock cable (arrow) from ignition
lock assembly.
- Remove center console trim panel.
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I Steering and Wheel Alignment
- Installation is reverse of removal, noting the following:
Replace shear bolts at steering column mounting bracket.
Tighten until bolt heads shear off.
Make sure
interlock cable snaps into place.
When installing column top trim panel, replace expansion
nut for trim retaining screw.
NOTE-
The steering angle sensor must be coded using a BMW scan
tool if it has been replaced.
A steering angle offset check
must then be carried out using the same
BMW scan tool.
CAUTION-
Check steering system for freedom of movement through en-
tire steering column
adiustment range.
Tightening torques Steering shaft coupler
to steering shaft 25 Nm (18 ft-lb)
(replace bolt)
Steering column to body
22 Nm (16 ft-lb)
Steering column adjustment motors,
removing and installing
Remove lower dash panel mounting fasteners (A) and (B).
- Lower panel and disconnect wiring harness from back side.
- Remove steering column lower trim panel. See Steering col-
umn trim, removing and replacing.
- Disconnect electrical harness from motor.
Remove motor mounting fasteners (arrows)
Slide motor to side and forward to remove.
Installation is reverse of removal.
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Steering and Wheel Alignment
Power assist is provided by a belt-driven pump at the lower
left front of the engine. The power steering fluid reservoir is lo-
cated at the left side of the engine compartment.
Power steering pump, removing and
installing
When working with power steering components, absolute
cleanliness is needed to ensure proper operation of the hy-
- Empty power steering fluid reservoir using clean syringe. Do
not reuse fluid.
- Raise front of car. Remove splash shield from under engine.
WARNING-
Make sure the car is firmly supported on jack stands de-
signed for the purpose. Place jack stands beneath structural
chassis points. Do not place jack stands under suspension
Darts.
Remove drive belt from power steering pump. See
020 Main-
tenance.
Remove alternator cooling duct
Remove fluid hoses from pump. Plug openings in pump and
hose ends.
Remove pump front mounting bolts
(A).
Remove fluid line support bracket (B)
Remove pump rear mounting bolt (arrow)
- Installation is reverse of removal, noting the following:
Make sure all thread bores, bolts, nuts, fluid couplings and
mating
surfaces are clean, and inside surface of multi-
ribbed-belt is free of grease and dirt.
Use new sealing washers when reattaching power steer-
ing pressure lines.
Make sure hoses have adequate clearance from chassis.
Install front pump fasteners.
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-
-steering and wheel -. Alignment I
< Hand tighten rear suppoll nut (arrow) against mounting
bracket.
Install rear mounting nut and tighten.
Do not over-torque banjo bolts.
* Fill and bleed power steering system as described later.
Tightening torques
Hydraulic lines to steering pump (banjo bolts)
a MlO 12 Nm (9 ft-lb)
. M14 35 Nm (26 ft-lb)
MI6 40 Nm (30 ft-lb)
. MI8 45 Nm (33 ft-lb)
Pump
brackets to engine block 25 Nm (18 ft-lb)
Rear pump support stud to pump housing
22 Nm (16 ft-lb)
Power steering system, bleeding and filling
- With engine off, fill power steering fluid reservoir with clean
fluid. Fill level to MAX
mark on dip stick.
- Start engine. Turn steering wheel twice to left lock and right I
lock.
- Recheck fluid level with engine off. Fill to MAX.
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i Steering and Wheel Alignment
RACK AND PINION STEERING
(6-CYLINDER MODELS)
Refer to the steering components illustration when perform-
ing the procedures below.
Rack and pinion steering
components
(6-cylinder models)
1. Power steering fluid reservoir
2. Fluid supply line
3. Power steering pump
4. Copper sealing ring
5. Banjo bolt MI4
6. Banjo bolt MI6
7. Power steering rack
8. Fluid return line
9. Pressurized fluid line
10. Steering fluid cooler
11. Rack boot components
12. Tie rod nut
13. Washer
14. Outer tie rod end
15. Tie rod locking ring
16. Outer tie rod end loclc nut
17. Inner tie rod
18. Hydraulic control valve
Steering rack, removing and installing
- Remove steering wheel as described earlier.
- Raise front of car, and remove front wheels.
WARNING -
Male sure the car is firmly supported on jack stands de-
signed for the purpose. Place jack stands beneath structural
chassis points. Do
not place jack stands under suspension
parts.
- Remove splash shield from under engine.
- Remove right and lefl engine mount fasteners
-" ., - , . ,
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/steering and Wheel Alignment
Raise engine approximately 40 mm (1.6 in). See 110 Engine
Removal and installation.
Remove right and left engine mounts and remove mount
brackets from subframe.
Empty power steering fluid reservoir using a clean syringe.
Do not reuse power steering fluid.
Remove right tie rod fastener (arrow) from right steering
Itnuckle. Repeat for left.
4 Press right tie rod out of right steering knucltle using BMW
special tool 31
2 240. Repeat for left.
/ ~ock nut Loclting ring
0012143
4 Malte reference measurement (A) of right tie rod end to tie
rod. Record measurement. Repeat for left.
NOJE-
0 Accurate measurement of tie rod end with reference to tie
rod will help approximate correct wheel alignment during
reassembly.
Note correct placement of inner taper on
locling ring
Remove fluid line
banjo bolts (arrows)
from steering rack.