
57STEERING
10
FAULT DIAGNOSIS VISUAL AND SAFETY CHECKS
WARNING: Before taking vehicle out on
the public highway for road test, it is
important that the following basic visual
checks are carried out to ensure that the vehicle
complies with legal requirements.
Tyres and wheel rims
1.Check and adjust tyre pressures.
See
GENERAL SPECIFICATION DATA,
Information, Tyre Pressures
Note that this information refers to standard tyres
fitted as original equipment.
2.Check condition of tyres. Inspect for signs of
uneven wear, damage and feathering. Check
tread depth.
3.Ensure that the tyre make, type and general
condition are common across each axle.
4.Check wheel rims for signs of damage and
excessive run out.
5.Carry out road test.
See Road Test Procedure
ROAD TEST PROCEDURE
General steering/handling problems can usually be
classified into one of the categories listed and ARE
GENERALLY RELATED TO THE AGE, CONDITION
AND USE OF THE VEHICLE.
WARNING: Ensure that all road tests are
conducted by suitably qualified drivers in
a safe and legal manner, and where local
traffic conditions allow.
1.Carry out visual and safety checks.
See Visual
and Safety Checks
Confirm general nature of complaint with customer,
simulating where possible the conditions under which
the problem occurs. Carry out following road test
procedure to establish the problem.2.Steering load assessment - drive at 16 km/h (10
mph). Put 90°turn input into steering wheel,
check self centering. The self centering should
be equal on each lock BUT not necessarily
return to exactly straight ahead without
assistance from the driver.
3.Steering assessment - drive at 64 km/h (40 mph)
on a staight FLAT road (no camber), check for
steering veer. The vehicle should follow a
straight path with NO tendency to follow a
curved path. If vehicle veers towards the kerb,
vehicle may be 'camber sensitive'. A small
amount of veer in direction of camber is
acceptable.
4.Directional stability assessment - drive at 112
km/h (70 mph) or maximum legal speed on a
straight flat road. Carry out a normal lane
change. Vehicle should quickly settle into a new
straight path.
5.Braking assessment (medium effort) - drive at 96
km/h (60 mph) on a straight flat road. Apply
steady medium braking effort, noting any
tendency to veer. Carry out brake test three
times, if a veer is consistently noted carry out a
braking efficiency test on a rolling road.
6.Braking assessment (full effort) - drive at 96
km/h (60 mph) on a straight flat road. Apply full
braking effort, noting any tendency to veer. Carry
out brake test three times, if a veer is
consistently noted carry out a braking efficiency
test on a rolling road.
If the symptom described by the customer is stiff
steering or steering niggle, carry out stiff steering
procedure.
See Stiff Steering Checklist
If not proceed with basic checks and adjustments.
See Visual Check and Basic Adjustments

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
1
ADJUSTMENT POWER STEERING BOX
Service repair no - 57.10.13
WARNING: Adjustments of steering box
should not be required while in warranty
period. If box is stiff or tight and within
warranty, it must be returned to manufacturer. No
attempt must be made to introduce backlash.
1.Apply park brake, select 'P' in automatic
transmission and chock wheels. Support chassis
front on axle stands.
2.Remove engine undertray.
3.Disconnect drag link from steering drop arm.
4.Check torque to turn.
See Fault diagnosis,
Stiff Steering Checklist
5.Centralise steering box.See Centralise
Steering Box
NOTE: Only check for no backlash when
steering box is in central position.
NOTE: If steering wheel is not straight, it
should be repositioned.
See Repair,
Steering Wheel
The adjustment of the steering box ensures
any preload or end float present on centre is
removed.
6.The adjustment is obtained by rocking the drop
arm about centre whilst an assistant slowly
tightens the steering box adjuster screw.
7.Tighten the locknut when all backlash has been
removed.
8.Repeat the check for backlash. If backlash exists
loosen locknut and repeat adjustment
procedure.
9.Turn steering wheel lock to lock and check no
tightness exists.
10.Ensure front wheels are aligned and in straight
ahead position.
See Front Wheel Alignment
11.Adjust drag link 924 mm between ball joint
centres.
12.Connect drag link. Tighten to
40 Nm.
13.Lower vehicle to ground level and remove
chocks.
14.Road test vehicle.
See Fault diagnosis, Road
Test Procedure
NOTE: If steering wheel is not in straight
ahead position when vehicle is travelling
in a straight line, drag link length is
incorrect and is pushing drop arm away from
central position.
Drag link adjust
15.Right hand drive vehicles - if steering wheel is to
right, drag link is too long. If steering wheel is to
left drag link is too short.
Left hand drive vehicles - if steering wheel is to
right, drag link is too short. If steering wheel is to
left drag link is too long.
16.Adjust drag link until steering wheel points
straight ahead when vehicle is travelling in a
straight line.
CENTRALISE STEERING BOX
1.To centralise the box, insert a suitable peg (hole
size 8.06 mm) into the rear of the drop arm and
into the steering box casing to enable rapid and
accurate setting on centre.

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.

FRONT SUSPENSION
3
REPAIR 7.Withdraw lower seating washer, rubber bush and
cupwasher.
8.Remove fixings, shock absorber to mounting
bracket.
9.Withdraw mounting bracket.
10.Lift off top seating washer, rubber bush and
cupwasher.
Refit
11.Reverse removal procedure. 1 to 10.FRONT ROAD SPRING
Service repair no - 60.20.11.
Remove
1.Remove front shock absorber.
See Front
Shock Absorber
CAUTION: Avoid over stretching brake
hoses. If necessary loosen hose connector
locknuts to allow hoses to follow axle.
2.Lower axle sufficient to free road spring.
3.Withdraw road spring.
4.Withdraw shock absorber bracket securing ring.
Refit
5.Fit shock absorber bracket retaining ring. Retain
in position with a nut.
6.Reverse 2 and 3.
7.Remove nut retaining securing ring.
8.Fit front shock absorber.

REAR SUSPENSION
1
REPAIR REAR ROAD SPRING
Service repair no - 64.20.01
Remove
1.Loosen rear road wheel retaining nuts.
2.Support chassis on stands and remove wheels.
3.Support rear axle weight with jack.
4.Disconnect shock absorbers at one end.
5.Position coil spring compressor correctly on road
spring.
6.Compress spring evenly to facilitate removal.
7.Lower axle to free road spring from upper seat.
CAUTION: Avoid lowering axle further than
rear brake flexible hose will allow.
8.Remove spring retainer plate.
9.Withdraw road spring, and spring isolator.
10.Lift off spring seat.
Refit
11.Reverse removal procedure.REAR SHOCK ABSORBER
Service repair no - 64.30.02.
Remove
1.Loosen road wheel retaining nuts.
2.Support chassis on stands. Remove road wheel
and support rear axle weight with jack.
3.Remove fixings and withdraw shock absorber
from axle bracket.
4.Remove upper fixings.
5.Withdraw shock absorber.
6.If required remove mounting bracket
7.If required remove mounting rubbers.
Refit
8.Reverse removal procedure.

BRAKES
1
DESCRIPTION AND OPERATION BRAKES
Discovery vehicles have servo assisted brake
systems and the option of an anti-lock brake system.
Information in this section refers to components
relevant to both brake systems. Where the system
components are different they are referred to as ABS
or NON ABS
BRAKE SYSTEM NON ABS
Description
The servo assisted hydraulic braking system is the
dual line type, incorporating primary and secondary
hydraulic circuits.
NOTE: References made to primary or
secondary do not imply main service
brakes or emergency brakes but denote
hydraulic line identification.
The brake pedal is connected to a vacuum assisted
mechanical servo which in turn operates a tandem
master cylinder. The front disc brake calipers each
house four pistons, these pistons are fed by the
secondary hydraulic circuit. The rear disc brake
calipers each house two pistons, these are fed by the
primary hydraulic circuit via a pressure reducing valve.
A brake fluid level switch is incorporated into the
reservoir cap assembly, the switch will immediately
illuminate a warning light in the instrument binnacle
indicating low fluid or sudden fluid loss.
The brake fluid reservoir is divided, the section closest
to the servo feeds the primary circuit and the section
furthest from the servo feeds the secondary circuit.
Under normal operating conditions both the primary
and secondary circuits operate simultaneously on
brake pedal application. In the event of a failure in the
primary circuit the secondary circuit will still function. If
the secondary circuit fails the primary circuit will still
function. The brake pedal travel will be longer in the
event of a half system failure.If the servo should fail, both hydraulic circuits will still
function but would require greater pedal effort due to
the lack of vacuum assistance. The hand operated
parking brake acts on a brake drum at the rear of the
transfer gearbox and is completely independent of the
hydraulic circuits.
Hydraulic circuit non ABS
Key
A = Primary hydraulic circuit
B = Secondary hydraulic circuit
C = Pressure reducing valve

70BRAKES
2
DESCRIPTION AND OPERATION ABS COMPONENTS
Location
Key to diagram
1. ABS Modulator unit
2. Servo/Master cylinder
3. Pressure reducing valve
4. Electronic control unit5. Rear sensors/exciter rings
6. Front sensors/exciter rings
7. Diagnostic plug connection