LAND ROVER DISCOVERY 1999 Workshop Manual

STEERING
57-48 REPAIRS
Ball joint - track rod
$% 57.55.07
Remove
1.Raise front of vehicle.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
2.Remove LH front road wheel.
3.Loosen adjuster clamp bolts.
4.Remove nut securing track rod ball joint to
steering knuckle.
5.Using tool LRT-57-036 break taper joint and
release track rod.
CAUTION: Before disconnecting any part of
the steering linkage, ensure the road wheels
are positioned straight ahead and the
steering wheel is prevented from turning.
Unrestricted turning of the steering wheel
will damage the SRS rotary coupler.
6.Unscrew ball joint and adjuster.
7.Remove clamps from adjuster and track rod. Refit
1.Clean adjuster, clamps and track rod.
2.Fit clamps to track rod and adjuster. Screw in
adjuster and ball joint.
3.Clean ball joint taper and taper seat.
4.Adjust length of track rod so that ball joint taper
is centralised in steering knuckle.
5.Fit track rod to steering knuckle and tighten nut
to 80 Nm (59 lbf.in).
6.Fit road wheel and tighten nuts to 140 Nm (103
lbf.ft).
7.Remove stand(s) and lower vehicle.
8.Check and, if necessary, adjust wheel
alignment.

+ STEERING, ADJUSTMENTS, Wheel
alignment - front.
9.After check/adjustment of wheel alignment,
ensure track rod adjuster clamp bolts are
tightened. Tighten M8 bolts to 22 Nm (16 lbf.ft)
and M10 bolts to 33 Nm (24 lbf.ft).

STEERING
REPAIRS 57-49
Ball joint - drag link
$% 57.55.15
Remove
1.Raise front of vehicle.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
2. RHD models: Remove LH front road wheel.
3. LHD models: Remove RH front road wheel.
4.Remove nut securing drag link to steering
knuckle.
5.Using LRT-57-036, break taper joint and
release drag link.
CAUTION: Before disconnecting any part of
the steering linkage, ensure the road wheels
are positioned straight ahead and the
steering wheel is prevented from turning.
Unrestricted turning of the steering wheel
will damage the SRS rotary coupler.
6.Loosen adjuster clamp bolts and unscrew ball
joint and adjuster.
7.Remove clamps from adjuster and drag link. Refit
1.Clean adjuster, clamps and drag link.
2.Fit clamps to drag link and adjuster. Screw in
adjuster and ball joint.
3.Clean ball joint taper and taper seat.
4.Adjust length of drag link so that ball joint taper
is centralised in steering knuckle.
5.Fit drag link to steering knuckle and tighten nut
to 80 Nm (59 lbf.ft).
6.Tighten drag link adjuster clamp bolts. Tighten
M8 bolts to 22 Nm (16 lbf.ft) and M10 bolts to
33 Nm (24 lbf.ft).
7.Check steering linkage is centralised.

+ STEERING, ADJUSTMENTS,
Steering linkage - centralise.
8.Fit road wheel and tighten nuts to 140 Nm (103
lbf.ft).
9.Remove stand(s) and lower vehicle.

STEERING
57-50 REPAIRS
Drag link
$% 57.55.17
Remove
1.Raise front of vehicle.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
2. RHD vehicles: Remove the LH front road
wheel.
3. LHD vehicles: Remove the RH front road
wheel.
4.Remove nut and bolt securing damper to drag
link and release damper.
5.Remove 2 nuts securing drag link to drop arm
and steering knuckle.
6.Using LRT-57-036 break taper joints and
remove drag link.
CAUTION: Before disconnecting any part of
the steering linkage, ensure the road wheels
are positioned straight ahead and the
steering wheel is prevented from turning.
Unrestricted turning of the steering wheel
will damage the SRS rotary coupler.7.Loosen adjuster clamp bolts and remove ball
joint and adjuster.
8.Remove clamps from adjuster and drag link.
Refit
1.Clean adjuster, clamps and ball joint.
2.Fit clamps to drag link and adjuster. Screw in
adjuster and ball joint.
3.Clean ball joint tapers and taper seats.
4.Fit drag link to drop arm and tighten nut to 80
Nm (59 lbf.ft).
5.Adjust length of drag link so that ball joint taper
is centralised in steering knuckle.
6.Fit drag link to steering knuckle and tighten nut
to 80 Nm (59 lbf.ft).
7.Tighten drag link adjuster clamp bolts. Tighten
M8 bolts to 22 Nm (16 lbf.ft) and M10 bolts to
33 Nm (24 lbf.ft)
8.Align damper to drag link, fit nut and bolt and
tighten to 125 Nm (92 lbf.ft).
9.Check steering linkage is centralised.

+ STEERING, ADJUSTMENTS,
Steering linkage - centralise.
10.Fit road wheel and tighten nuts to 140 Nm (103
lbf.ft).
11.Remove stand(s) and lower vehicle.

STEERING
REPAIRS 57-51
Damper - steering
$% 57.55.21
Remove
1.Raise front of vehicle.
WARNING: Do not work on or under a
vehicle supported only by a jack. Always
support the vehicle on safety stands.
2.Remove 2 nuts and bolts securing steering
damper to drag link and chassis.
3.Compress damper and remove from vehicle.
Refit
1.Position damper to chassis and drag link. Fit
nuts and bolts and tighten to 125 Nm (92 lbf.ft).
2.Remove stand(s) and lower vehicle.

STEERING
57-52 REPAIRS
Steering wheel
$% 57.60.01.30
Remove
1.Remove drivers airbag.

+ RESTRAINT SYSTEMS, REPAIRS,
Airbag module - drivers.
2.Disconnect horn multiplug.
3.Centralise steering wheel with road wheels in
straight ahead position.
4.Restrain steering wheel and loosen self locking
nut securing steering wheel to column.
5.Release steering wheel from column.
6.Remove and discard self locking nut.
7.Remove steering wheel.
8.Attach tape across edge of rotary coupler to
retain correct setting. 9.Release 2 clips securing each horn button to
steering wheel.
10.Remove screw securing horn earth lead to
steering wheel.
11.Disconnect radio and cruise control multiplugs.
12.Remove 2 screws securing radio switches to
steering wheel.
13.Remove radio switches from steering wheel.
14.Remove 2 screws securing cruise control
switches to steering wheel.
15.Remove cruise control switches from steering
wheel.
16.Remove horns from steering wheel.
Refit
1.Fit horn switches to steering wheel and secure
with clips.
2.Fit and tighten screw securing horn earth lead
to steering wheel.
3.Fit cruise control switches to steering wheel
and secure with screws.
4.Fit radio switches to steering wheel and secure
with screws.
5.Connect radio and cruise control multiplugs.
6.Remove tape from rotary coupler.
7.Ensure road wheels are in straight ahead
position and indicator cancelling cam are
aligned horizontally.
8.Fit steering wheel to column.
9.Connect horn multiplug.
10.Fit and tighten new self locking nut securing
steering wheel to column to 43 Nm (32 lbf.ft).
11.Fit drivers airbag.

+ RESTRAINT SYSTEMS, REPAIRS,
Airbag module - drivers.

FRONT SUSPENSION
DESCRIPTION AND OPERATION 60-1
FRONT SUSPENSION DESCRIPTION AND OPERAT ION
Front suspension component layout
(ACE torsion bar shown)
1Turret RH
2Radius arm LH
3Anti-roll bar link LH
4Damper LH
5Turret LH
6Coil spring LH
7Torsion/anti-roll bar
8Steering knuckle
9Steering damper
10Drag link
11ACE short arm (if fitted)12Panhard rod
13ACE long arm (if fitted)
14Steering knuckle
15Brake caliper and hub assembly
16Radius arm RH
17Coil spring RH
18ACE actuator
19Anti-roll bar link RH
20ACE actuator
21Anti-roll bar link RH

FRONT SUSPENSION
60-2 DESCRIPTION AND OPERATION
Front suspension components (ACE
torsion bar shown)

FRONT SUSPENSION
DESCRIPTION AND OPERATION 60-3
1Damper 2 off
2Bolt 2 off
3Turret 2 off
4Nut 8 off
5Nut
6Bolt 4 off
7Nut
8Washer
9Anti-roll bar link RH
10Torsion/Anti-roll bar assembly
11Anti-roll bar link LH
12Washer
13Nut
14Nut
15Mounting rubber 2 off
16Clamp plate 2 off
17Bolt 2 off
18Lower spring seat LH
19Front axle20Nut
21Bush
22Panhard rod
23Bolt
24Radius arm LH
25Bolt
26Bush
27Nut
28Nut
29Bush
30Bolt
31Radius arm RH
32Bolt
33Bush
34Nut
35Lower spring seat RH
36Coil spring 2 off
37Upper spring seat 2 off

FRONT SUSPENSION
60-4 DESCRIPTION AND OPERATION
Description
General
The front suspension comprises two dampers and coil springs, two radius arms, a Panhard rod and an anti-roll bar.
The front axle provides the location points for the dampers, springs, radius arms and the Panhard rod.
The anti-roll bar assembly is an essential part of the front suspension. On vehicles without Active Cornering
Enhancement (ACE) a conventional 'passive' anti-roll bar is fitted. On vehicles fitted with the ACE system, a thicker
diameter anti-roll bar, known as a torsion bar, is used with an actuator at one end.

+ FRONT SUSPENSION, DESCRIPTION AND OPERATION, Description - ACE.
The hydraulic dampers and coil springs provide springing for each front wheel. The long travel dampers, springs and
radius arms provide maximum axle articulation and wheel travel for off-road driving. The front axle is controlled
longitudinally by two forged steel radius arms and transversely by a Panhard rod.
Radius arms
Each radius arm is manufactured from forged steel. Two bushes are pressed into the forward end of the radius arm.
The forward end of the radius arm is located in a fabricated bracket on the axle and secured through the bushes with
two bolts and nuts. A bush is pressed into the rear of the radius arm which is also located in a fabricated bracket on
each chassis longitudinal and secured through the bush with a bolt and nut.
The radius arms prevent longitudinal movement of the front axle and because of their length allow maximum axle
articulation. The stiffness of the bushes in each radius arm also contributes to the vehicle roll stiffness.
Each radius arm has a notch on its lower edge which provides location for the vehicle jack.
Dampers
Two conventional telescopic dampers are used to control body/axle movement. A turret is located on a bracket welded
to the chassis. The upper spring seat has four studs which pass through holes in the bracket and align with
corresponding holes in the turret. Four nuts are screwed onto the studs and secure the turret and upper spring seat
to the chassis.
A fabricated platform is welded to the axle. The platform has two captive nuts which provide for the attachment of the
damper. A lower spring seat is located on the platform. Each spring seat is handed and has a bracket which secures
the ABS sensor harness and the front brake hose.
Each damper is fitted with a bush at its upper end. The bush locates in the top of the turret and is secured with a cross
bolt. The lower attachment point for the damper is also fitted with a bush. This bush has a spindle through its centre
with a hole at each end. The spindle is seated on the lower spring seat and the axle platform and secured with two
bolts. The coil spring is fitted in a compressed state between the upper and lower spring seats and assists the damper
in controlling the body/axle movement. The upper and lower bushes are replaceable items.
Rubber bump stops are fitted to the chassis above each end of the axle. The bump stops are progressive in their
compression and prevent the axle from contacting the chassis in the event of maximum suspension travel being
reached. The bump stops revert to their original shape once the compression load has been removed from them.
The damper functions by restricting the flow of a hydraulic fluid through internal galleries within the damper body. A
chromium plated rod moves axially within the damper. As the rod moves, its movement is limited by the flow of fluid
through the galleries thus providing damping of undulations in the terrain. The damper rod is sealed at its exit point
from the body to maintain fluid within the unit and prevent the ingress of dirt and moisture. The seal also acts as a
wiper to keep the rod outer diameter clean. A plastic shroud protects the rod and slides over the body as the damper
moves. The coil spring aids the damper to extend after being compressed and also aids the damping process.

FRONT SUSPENSION
DESCRIPTION AND OPERATION 60-5
Coil springs
Coil springs are fitted to the front axle of the vehicle. The front springs differ between petrol and Diesel variants. Each
spring is retained at its base by the lower spring seat. The top of each spring is located in the upper spring seat
isolator. The upper spring seat is manufactured from natural rubber , with a bonded metal plate and four bonded studs
which provide for the attachment of the damper turret. The rubber isolator reduces noise transmitted to the chassis
and body from the suspension.
The coil springs must be installed correctly. The bottom coil of the spring locates in a recess in the lower spring seat.
The top coil of the spring is ground flat to locate the upper spring seat isolator.
Coil Spring Specifications – Models up to 03 Model Year
The front springs on petrol variants are manufactured from carbon chrome 13.9 mm (0.55 in) diameter bar. The spring
has 7.6 coils and a free length of 377 mm (14.8 in). The petrol front spring is identified by a pink and orange stripe
painted on a number of coils.
The front springs on Diesel variants are manufactured from carbon chrome 13.9 mm (0.55 in) diameter bar. The spring
has 7.6 coils and a free length of 383 mm (15.0 in). The Diesel front spring is identified by a white and purple stripe
painted on a number of coils.
Coil Spring Specifications – Models from 03 Model Year
The introduction of the 03MY vehicle introduced a range of additional spring fitments. These were introduced to cover
the introduction of the 4.6l V8 engine, the fitment of a front mounted winch and to optimise the vehicle trim heights.
The coil springs are manufactured from silicon manganese 13.8 mm or 13.9 mm (0.54 in or 0.55 in) diameter bar. The
following spring data table shows the colour codes, number of coils and spring free length.
Spring Data
The following table shows spring fitment applicablity.
Spring Fitment Applicability
The following table shows standard springs and uprated springs required when a front winch is fitted.
Winch Fitment Spring Applicability
Colour Code Total No. of Coils Free Length
Red/Purple 7.4 371 mm (14.6 in)
Yellow/Purple 7.4 378.4 mm (14.9 in)
Blue/Purple 7.4 365 mm (14.4 in)
Grey/Purple 7.4 387 mm (15.2 in)
Purple/Purple 7.4 373.8 mm (14.7 in)
Yellow/Orange 7.4 394.6 mm (15.5 in)
Green/Orange 7.4 382.6 mm (15 in)
Pink/Brown 7.6 405.6 mm (15.9 in)
Left Hand Drive Right Hand Drive
RH side LH side RH side LH side
Red/Purple Red/Purple Yellow/Purple Blue/Purple
Yellow/Purple Yellow/Purple Grey/Purple Purple/Purple
Grey/Purple Grey/Purple Yellow/Orange Green/Orange
Standard Spring Winch Fitted Spring
RH Side LH Side Both Sides
Red/Purple Red/Purple Grey/Purple
Yellow/Purple Blue/Purple Yellow/Orange
Yellow/Purple Yellow/Purple Yellow/Orange
Grey/Purple Purple/Purple Green/Orange
Grey/Purple Grey/Purple Green/Orange
Yellow/Orange Green/Orange Pink/Brown