1995 LAND ROVER DISCOVERY ECU

FRONT AXLE AND FINAL DRIVE
11
OVERHAUL Fit driveshaft and stub axle
59.Insert axle shaft, and when differential splines
are engaged, push assembly in fully.
CAUTION: Take care not to damage axle
shaft oil seals.
60.Place a new joint washer in position on swivelpin
housing to stub axle mating face. Coat threads
of stub axle bolts with Loctite 270.
61.Fit stub axle with flat at 12 o'clock position.
CAUTION: Ensure that constant velocity
joint bearing journal is butted against
thrust ring on stub axle. Before stub axle
is secured.
62.Place mud shield in position and secure stub
axle to swivel pin housing with six bolts and
tighten evenly to
65 Nm.
63.Fit brake jump hoses to brake jump hose
bracket.
64.Fit front hub complete assembly.
See Repair,
Front Hub Assembly
65.Check swivel pin housing oil drain plug is fitted.
66.Fill swivel assembly to correct level, with new oil.
See SECTION 10, Maintenance, Under
Vehicle Maintenance
67.Set steering lock stop bolts to provide a
clearance of 20mm.
See STEERING,
Adjustment, Steering Lock Stops
68.Fit ABS brake sensor.See BRAKES, Repair,
Sensors - Front

STEERING
5
DESCRIPTION AND OPERATION Rotary valve operation
The rotary valve assembly seen in RR3620M
comprises the worm (1), the valve sleeve (2), the input
shaft (4) and the torsion bar (5).
The valve sleeve is retained inside the worm by the
trim screw (3), and incorporates valve ports in its inner
bore. The input shaft is attached to the steering wheel
via the steering shaft and steering column and
incorporates valve ports in its outer diameter to align
with those in the sleeve. The torsion bar which is
secured to the worm and input shaft with pins (6) at
each end (later models use one pin at input shaft
end), holds the valve ports in neutral alignment when
there is no demand for assistance.No demand for assistance (Valve at neutral)
When there is no demand for assistance as seen in
RR3620M, the torsion bar holds the input shaft and
sleeve valve ports in neutral relationship to one
another, allowing equal pump pressure A to both
sides of the piston/rack (9). Any excess fluid flow from
the pump returns to the reservoir via B.
Rotary valve at neutral

STEERING
5
FAULT DIAGNOSIS Symptom :-
Steering excessively light/sensitive. Excessive
freeplay at steering wheel.
1.Are steering box adjustments correct?
NO -
See Adjustment, Power Steering Box
WARNING: Adjustments of steering box
should not be required while in warranty
period. If box is within warranty, it must be
returned to manufacturer. No attempt must be
made to introduce backlash.
YES - Suspect worn panhard rod or radius arm
bushes Check condition of ball joints and
the lower steering column shaft universal
joints for wear.
See Repair, Lower
Steering Shaft and Universal Joints
Symptom :-
Steering vibration, road wheel shimmy - wobble.
Vibration through the steering linkage powerful
enough to induce high frequency oscillation of the
steering wheel, is generally caused by out of balance
road wheels. However there are a number of other
possible causes of this symptom which if severe, may
be described as shimmy or wobble. Regardless of the
terminology used by the owner/driver to describe the
symptoms, the following diagnostic checks should be
carried out in the order presented.
1.Check the tyres and balance of the road wheels.
See GENERAL SPECIFICATION DATA,
Information, Wheels and Tyres See
WHEELS AND TYRES, Fault diagnosis, Fault
- Symptoms See WHEELS AND TYRES,
Repair, Wheel Balancing
2.Check the steering hydraulic damper function.
See Steering Damper
3.Check steering column universal joints for wear
and correct alignment.
See Repair, Lower
Steering Shaft and Universal Joints
4.Check steering linkage ball joints for wear,
correct alignment and security, including steering
box and tie rod.
See Steering Linkage Inspect
5.Check all front suspension rubbers for wear.
Check all fixing torques, including radius arm
bushes, panhard rod and anti-roll [sway] bar.
See FRONT SUSPENSION, Repair, Panhard
Rod See FRONT SUSPENSION, Repair,
Radius Arm See FRONT SUSPENSION,
Repair, Anti-Roll[Sway] Bar Assembly See
FRONT SUSPENSION, Repair, Front Shock
Absorber
6.Fit new radius arm bushes using NTC 6860. Fit
harmonic damper if vehicle has air suspension.
Fit new nuts, bolts and washers.
7. Coil spring vehicles only- If problem persists
fit damper kit STC 241 (2 off front) and STC
1474 (2 off rear). Road test vehicle.
8.Check the power steering box adjustments and
operation.
See Overhaul, Power Steering Box
9.Check the hub bearing end floats and determine
the condition of the hub bearings. As applicable.
See FRONT AXLE AND FINAL DRIVE, Repair,
Front Hub Assembly
10.Check the resistance and condition of the
swivels.
See FRONT AXLE AND FINAL
DRIVE, Description and operation,
Description
If problem is not diagnosed: Repeat
checks starting at 1.
11.Carry out a full steering geometry check.
See
INTRODUCTION, Information, Steering

57STEERING
12
FAULT DIAGNOSIS Steering column alignment
1.Place vehicle on level ground. Measure the
angle of lower steering shaft using a Pernumeter
placed on the shaft between the universal joints.
The angle should measure a minimum of 12Ê.
2.If necessary, realign the shaft. Release the five
fixings securing the steering column. Position
column as required. Tighten the fixings evenly,
27 Nm.
3.Loosen the three screws securing lower steering
column shroud to upper shroud ensure lower
shroud is clipped to upper shroud. Reposition
shroud, tighten screws.
4.Recheck steering column angle.
Steering box adjustment
1.Check steering box adjustment.
See
Adjustment, Power Steering Box
Steering damper check
1.Check condition of steering damper
See
Steering Damper
VISUAL CHECK AND BASIC ADJUSTMENTS
NOTE: It is important that the following
instructions are carried out in the
sequence shown and the results recorded.
1.Road springs - check that road springs are
correctly seated and are to correct specification
for vehicle. For spring specification.
See
GENERAL SPECIFICATION DATA,
Information, Road Springs Data
2.Ride height - measure trim height from wheel
centre to wheelarch eyebrow. Record results on
data sheet.
3.Check/top up power steering fluid
See Repair,
Power Steering Fluid Reservoir
4.Check tension and condition of drive belt.See
ENGINE, Repair, Drive Belt
5.Track rod/drag link - check condition of track rod,
drag link and ball joints.
See Repair, Drag Link
and Drag Link Ends
If either component is damaged, check operation
of steering damper and steering box for
smoothness. Replace all damaged or worn
components that impair the operation of the
steering system.
6.Suspension bushes - examine all steering and
suspension bushes for signs of wear and
deterioration. Also check all fixings for torque
relaxation. Tighten to correct torque value.
See
FRONT SUSPENSION, Specifications, torque,
Torque Values
7.Oil leaks - check front and rear axle hubs for
leak and repair as necessary.
8.Brake system - check brake system for leaks,
pipe condition, pad wear/contamination, disc
wear/condition and ABS sensors for correct
fitting.
9.Hub end float - check movement in the hubs by
rocking the wheels.
10.Check front wheel alignment. Vehicles displaying
a tendency to veer more than considered
allowable, it is permissible to set the front track
to parallel.
11.Having completed all the above checks and
adjustments, road test vehicle.
See Road Test
Procedure
Attempting to reproduce the symptoms
established earlier. If symptoms still exist refer to
relevant Diagnostic Chart.

STEERING
13
FAULT DIAGNOSIS STEERING LINKAGE INSPECT
NOTE: When inspecting steering linkages
and ball joints for wear the following items
must be checked.
Steering ball joints
1.Check ball joint rubber boots for security, signs
of cracking or deterioration.
2.Check ball joint assemblies for seizure i.e. no
movement on ball joint and associated
assemblies.
3.Check for excessive wear. This will be evident
as extreme movement on track rod and steering
linkages. Renew parts as necessary.
See
Repair, Track Rod and Linkage See Repair,
Drag Link and Drag Link Ends
Steering linkages
4.Check all linkages for wear, deterioration and
damage. Renew parts as necessary.
See
Repair, Track Rod and Linkage See Repair,
Drag Link and Drag Link Ends

57STEERING
2
REPAIR POWER STEERING BOX
Service repair no - 57.10.01
General precautions
1.Whenever any part of system, is removed or
disconnected, utmost cleanliness must be
observed.
2.Disconnected ports and hoses must be plugged
to prevent ingress of dirt. If metal sediment is
found in system, establish cause rectify and
flush system.
3.Do not start engine until reservoir is full as pump
will be damaged.
4.Metric pipe fittings are used with 'O' ring pipe
ends on fittings to steering box.
5.Follow normal 'O' ring replacement procedure
whenever pipes are disconnected.
6.Ensure compatible metric components when
fitting replacement pipes.
CAUTION: Before removing any parts of
steering linkage, it is imperative that road
wheels are positioned straight ahead.
Then steering wheel removed to prevent rotary
coupler being wound up or damaged.
CAUTION: After refitting steering linkage
parts follow correct procedure to ensure
that road wheels, steering box and
steering wheel are correctly positioned relative to
each other when in straight ahead condition. If
steering wheel requires repositioning, ensure that
drive pegs on rotary coupler are correctly
positioned before steering wheel is replaced.
This ensures drive pegs locate in their holes in
rear of steering wheel.
After final alignment connect rotary coupler
multiplug, tighten steering wheel securing nut and
fit air bag - if fitted or steering wheel trim pad.
NOTE: When drag link is disconnected
from steering box, travel available at
steering wheel to each full lock is not
equal.
Remove
1.Site vehicle on level surface.
2.Open bonnet[hood].
3.Remove filler cap from power steering fluid
reservoir.
4.Clean steering box.
5.Disconnect feed and return pipes from steering
box.
6.Plug open pipes and steering box ports to
prevent ingress of dirt.
7.Support chassis front on axle stands. Or raise
vehicle on a hoist.
WARNING: Ensure wheels are chocked,
parking brake is applied, and low range
selected.

STEERING
3
REPAIR 8.Remove undertray
9.Disconnect drag link from drop arm using a
suitable extractor.
10.Remove pinch bolt securing lower shaft
universal joint to power steering box.
11.Loosen but do not remove nut securing tie bar to
mounting.
12.Remove bolts securing tie bar, move tie bar
aside.
13.Remove bolts securing power steering box to
chassis side member.
14.Withdraw power steering box.

57STEERING
4
REPAIR
Refit
15.Position steering box to chassis side member,
ensuring locating peg is engaged. Tighten bolts
to
81 Nm.
16.Fit pinch bolt and nut securing universal joint to
power steering box. Tighten to
25 Nm.
17.Position tie bar, tighten bolts and nut to81 Nm,
starting with tie bar to mounting nut, then
loosen nut and bolts by one complete turn.
18.Check steering box, adjust if necessary.See
Adjustment, Power Steering Box
19.Refit drag link to drop arm tighten nut to40 Nm.
20.Fit undertray.
21.Lower vehicle to ground.
22.Remove plugs and refit pipes to steering box.
Tighten 16mm thread to
20 Nm.
14mm thread to15 Nm.
23.Remove filler cap. Fill reservoir to oil level mark
on dipstick. Use recommended fluid.
See
LUBRICANTS, FLUIDS AND CAPACITIES,
Information, Recommended Lubricants and
Fluids
and bleed power steering system.See
Power Steering System - Bleed
24.Recheck fluid level and replace cap.
25.With engine running, test steering system for
leaks by holding steering in both full lock
directions.
CAUTION: Do not maintain this pressure
for more than 30 seconds in any one
minute, to avoid oil overheating and
possible seal damage.
26.Test drive vehicle: using both full lock directions,
to settle steering components. If possible, drive
vehicle over speed bumps and include harsh
braking.
WARNING: Do not test drive vehicle on
public highway.
27.Drive vehicle in a straight line on level ground
and stop.
28.Tighten tie bar to mounting nut to
110 Nm.
29.Tighten bolts securing tie bar to81 Nm.
30.Ensure steering wheel is correctly aligned when
wheels are positioned straight ahead.
31.If necessary reposition steering wheel.
See
Steering Wheel
32.Road test vehicle.