suspension LAND ROVER DISCOVERY 1999 Workshop Manual

CONTENTS
CONTENTS 1
INTRODUCTION ...................................................................................... 01-1
How To Use This Manual................................................................................................................ 01-1
Repairs and Replacements ............................................................................................................. 01-2
Specifications .................................................................................................................................. 01-2
Abbreviations and Symbols ............................................................................................................ 01-3
GENERAL INFORMATION ...................................................................... 03-1
General Precautions ....................................................................................................................... 03-1
Safety Instructions .......................................................................................................................... 03-2
Environmental Precautions ............................................................................................................. 03-3
General Fitting Instructions ............................................................................................................. 03-6
Ball and Roller Bearings ................................................................................................................. 03-7
Oil Seals.......................................................................................................................................... 03-8
Joints and Joint Faces .................................................................................................................... 03-9
Locking Devices .............................................................................................................................. 03-9
Screw Threads ................................................................................................................................ 03-10
Bolt and Nut Identification ............................................................................................................... 03-11
Flexible Pipes and Hoses ............................................................................................................... 03-13
Rolling Road Testing....................................................................................................................... 03-15
Fuel Handling Precautions .............................................................................................................. 03-16
Electrical Precautions ..................................................................................................................... 03-17
Supplementary Restraint System Precautions ............................................................................... 03-18
SRS Component Replacement Policy ............................................................................................ 03-23
Air Conditioning System Precautions .............................................................................................. 03-24
Air Conditioning Compressor Replacement .................................................................................... 03-26
Body Repairs .................................................................................................................................. 03-27
GENERAL DATA ..................................................................................... 04-1
Engine - Td5 ................................................................................................................................... 04-1
Engine - V8 ..................................................................................................................................... 04-4
Fuel system - Td5 ........................................................................................................................... 04-8
Fuel system - V8 ............................................................................................................................. 04-8
Cooling system - Td5 ...................................................................................................................... 04-9
Cooling system - V8 ........................................................................................................................ 04-10
Clutch - Td5 .................................................................................................................................... 04-11
Clutch - V8 ...................................................................................................................................... 04-12
Manual gearbox - R380 .................................................................................................................. 04-13
Transfer box - LT230SE .................................................................................................................. 04-14
Automatic gearbox - ZF4HP22/24 .................................................................................................. 04-15
Rear axle......................................................................................................................................... 04-16
Front axle ........................................................................................................................................ 04-16
Steering........................................................................................................................................... 04-17
Suspension ..................................................................................................................................... 04-18
Brakes ............................................................................................................................................. 04-19
Wheels and tyres ............................................................................................................................ 04-20
Air conditioning ............................................................................................................................... 04-21
Electrical - Td5 ................................................................................................................................ 04-22
Electrical - V8 .................................................................................................................................. 04-22
Dimensions ..................................................................................................................................... 04-23
Weights ........................................................................................................................................... 04-24

CONTENTS
2CONTENTS
IDENTIFICATION NUMBERS .................................................................. 05-1
Vehicle Identification Number ......................................................................................................... 05-1
Identification Number Locations ..................................................................................................... 05-3
TORQUE WRENCH SETTINGS .............................................................. 06-1
Maintenance ................................................................................................................................... 06-1
Engine Td5 ..................................................................................................................................... 06-2
Engine V8 ....................................................................................................................................... 06-4
Emission control - Td5 .................................................................................................................... 06-5
Emission control - V8 ...................................................................................................................... 06-5
Engine management system - Td5 ................................................................................................. 06-6
Engine management system - V8................................................................................................... 06-6
Cooling system ............................................................................................................................... 06-7
Manifolds and exhaust systems - Td5 ............................................................................................ 06-8
Manifolds and exhaust systems - V8 .............................................................................................. 06-8
Clutch.............................................................................................................................................. 06-9
Manual gearbox - R380 .................................................................................................................. 06-10
Transfer box - LT230SE ................................................................................................................. 06-11
Automatic gearbox - ZF4HP22 ....................................................................................................... 06-12
Propeller shafts ............................................................................................................................... 06-13
Axles ............................................................................................................................................... 06-13
Steering .......................................................................................................................................... 06-14
Front suspension ............................................................................................................................ 06-15
Rear suspension ............................................................................................................................. 06-16
Brakes............................................................................................................................................. 06-17
Restraint systems ........................................................................................................................... 06-18
Body................................................................................................................................................ 06-19
Heating and air conditioning ........................................................................................................... 06-20
Wipers and washers ....................................................................................................................... 06-20
Electrical ......................................................................................................................................... 06-21
LIFTING AND TOWING ........................................................................... 08-1
LIFTING .......................................................................................................................................... 08-1
TOWING ......................................................................................................................................... 08-2
TRANSPORTING ........................................................................................................................... 08-4
CAPACITIES, FLUIDS, LUBRICANTS AND SEALANTS ...................... 09-1
Capacities ....................................................................................................................................... 09-1
Fluids .............................................................................................................................................. 09-2
Anti-Freeze Concentration .............................................................................................................. 09-2
Lubrication ...................................................................................................................................... 09-3
Sealants .......................................................................................................................................... 09-4

CONTENTS
CONTENTS 3
MAINTENANCE ........................................................................................ 10-1
PROCEDURES
V8 engine underbonnet view .......................................................................................................... 10-1
Diesel underbonnet view ................................................................................................................. 10-2
Seats and seat belts ...................................................................................................................... 10-3
Lamps, horns and warning indicators ............................................................................................. 10-5
Wipers and washers ...................................................................................................................... 10-5
Handbrake .................................................................................................................................. 10-6
Alarm handset battery ..................................................................................................................... 10-6
Road wheels ................................................................................................................................... 10-6
Tyres .............................................................................................................................................. 10-6
Brake pads, discs and calipers ....................................................................................................... 10-6
Road wheel speed sensors ............................................................................................................. 10-7
Brake fluid ....................................................................................................................................... 10-7
Fuel filter - diesel engine ................................................................................................................. 10-7
Fuel filter sedimenter ...................................................................................................................... 10-7
Road wheels ................................................................................................................................... 10-8
Radiator/Intercooler ........................................................................................................................ 10-8
Ambient air Temperature and pressure sensor .............................................................................. 10-8
Doors, bonnet and fuel filler flap ..................................................................................................... 10-8
Air suspension intake filter .............................................................................................................. 10-9
Anti-freeze....................................................................................................................................... 10-9
Cooling system ............................................................................................................................... 10-9
Spark plugs - V8 engine.................................................................................................................. 10-10
Air cleaner - V8 engine ................................................................................................................... 10-10
Air cleaner and dump valve - diesel engine .................................................................................... 10-10
Auxiliary drive belt ........................................................................................................................... 10-11
Auxiliary drive belt - V8 engine ....................................................................................................... 10-11
Auxiliary drive belt - diesel engine .................................................................................................. 10-11
Fluid reservoirs ............................................................................................................................... 10-12
Steering box .................................................................................................................................... 10-13
Battery ............................................................................................................................................. 10-13
Intercooler - diesel engine............................................................................................................... 10-14
Engine oil - V8 engine ..................................................................................................................... 10-14
Engine oil - diesel engine ................................................................................................................ 10-15
Centrifuge rotor – diesel engine ...................................................................................................... 10-15
Engine oil filter - diesel engine ........................................................................................................ 10-16
Engine oil filter – V8 engine ............................................................................................................ 10-16
Manual gearbox .............................................................................................................................. 10-17
Automatic gearbox ......................................................................................................................... 10-18
Transfer box .................................................................................................................................... 10-19
Front and rear axle .......................................................................................................................... 10-20
Propeller shafts ............................................................................................................................... 10-20
Anti-roll bar links ............................................................................................................................. 10-22
ACE actuators ................................................................................................................................. 10-23
ACE filter ......................................................................................................................................... 10-23

CONTENTS
4CONTENTS
Brake hose, brake, fuel, ACE, clutch pipes and unions/electrical harnesses ................................ 10-24
Engine, gearbox, transfer box and axles ........................................................................................ 10-25
Exhaust system .............................................................................................................................. 10-25
Steering box and front suspension ................................................................................................. 10-25
Steering rod ball joints ................................................................................................................... 10-27
Dampers and SLS height sensors .................................................................................................. 10-27
Front and rear axle suspension links .............................................................................................. 10-28
Towing bracket ............................................................................................................................... 10-29
Engine mountings - V8 engine........................................................................................................ 10-30
Road/roller test ............................................................................................................................... 10-31

CONTENTS
CONTENTS 15
FRONT SUSPENSION.............................................................................. 60-1
DESCRIPTION AND OPERATION
Front suspension component layout (ACE torsion bar shown) ....................................................... 60-1
Front suspension components (ACE torsion bar shown) ................................................................ 60-2
Description ...................................................................................................................................... 60-4
DESCRIPTION AND OPERATION
ACE system component layout ....................................................................................................... 60-7
ACE system control diagram .......................................................................................................... 60-8
Description - ACE ........................................................................................................................... 60-9
Operation ........................................................................................................................................ 60-22
ADJUSTMENTS
ACE hydraulic system bleeding ..................................................................................................... 60-25
Fluid level check - ACE system ...................................................................................................... 60-25
REPAIRS
Bushes - Panhard rod ................................................................................................................... 60-27
Ball joint - upper - steering knuckle ............................................................................................... 60-28
Ball joint - lower - steering knuckle ................................................................................................. 60-29
Steering knuckle ........................................................................................................................... 60-30
Road spring - front ........................................................................................................................ 60-32
Wheel hub ....................................................................................................................................... 60-33
Damper - front ............................................................................................................................... 60-35
Bushes - radius arm ...................................................................................................................... 60-37
ECU - ACE ..................................................................................................................................... 60-39
Accelerometer - ACE - upper ........................................................................................................ 60-40
Accelerometer - ACE - lower ........................................................................................................ 60-40
Pump - ACE - V8 ............................................................................................................................ 60-41
Pump - ACE - diesel ....................................................................................................................... 60-42
Valve block - ACE ......................................................................................................................... 60-44
Filter - high pressure - ACE .......................................................................................................... 60-47
Pressure transducer - ACE ........................................................................................................... 60-48
Solenoid - pressure control valve - ACE ....................................................................................... 60-49
Solenoid - directional control valve - ACE ..................................................................................... 60-49
Pipe assembly - valve block to front actuator - ACE ...................................................................... 60-50
Pipe assembly - pump or reservoir to valve block - ACE - V8 ....................................................... 60-52
Pipe assembly - pump or reservoir to valve block - ACE - diesel .................................................. 60-55
Pipe assembly - valve block to rear actuator - ACE ........................................................................ 60-59
Actuator - front - ACE .................................................................................................................... 60-61
Bushes - front long arm - ACE ........................................................................................................ 60-63

CONTENTS
16 CONTENTS
REAR SUSPENSION ................................................................................ 64-1
DESCRIPTION AND OPERATION
Rear suspension component layout (vehicles with SLS) ............................................................... 64-2
Rear suspension component layout (vehicles without SLS) .......................................................... 64-3
Rear suspension components ........................................................................................................ 64-4
Description ...................................................................................................................................... 64-6
DESCRIPTION AND OPERATION
SLS component layout.................................................................................................................... 64-9
SLS system control diagram ........................................................................................................... 64-10
Description - SLS ............................................................................................................................ 64-12
Operation ........................................................................................................................................ 64-21
ADJUSTMENTS
SLS calibration blocks .................................................................................................................... 64-25
REPAIRS
Wheel hub....................................................................................................................................... 64-27
Road spring - rear ........................................................................................................................... 64-29
Air spring - SLS............................................................................................................................... 64-30
Damper - rear ............................................................................................................................... 64-31
Bushes - radius arm ....................................................................................................................... 64-31
Bushes - Watts linkage ................................................................................................................. 64-34
Sensor - height - SLS ..................................................................................................................... 64-35
Compressor unit - air - SLS ............................................................................................................ 64-35
Filter - intake - SLS ......................................................................................................................... 64-37
Switch - ride height ......................................................................................................................... 64-37
Air valve - SLS ................................................................................................................................ 64-38
Actuator - rear - ACE ...................................................................................................................... 64-39
Bushes - rear long arm - ACE......................................................................................................... 64-41

INTRODUCTION
01-1
INTRODUCTION
How To Use This Manual
Introduction
This Manual is designed to assist skilled technicians
in the efficient repair and maintenance of Discovery
vehicles.
Individuals who undertake their own repairs should
have some skill and training, and limit repairs to
components which could not affect the safety of the
vehicle or its passengers. Any repairs required to
safety critical items such as steering, brakes,
suspension or supplementary restraint system
should be carried out by a Land Rover Dealer.
Repairs to such items should NEVER be attempted
by untrained individuals.
General
To assist in the use of this Manual, it is divided into
sections and sub-sections. The section title is given
at the top of each page and the relevant sub-section
is given at the bottom.
There is a single contents section at the front of the
Manual, which is divided by section and sub-section.
Each section is numbered from page 1.
The individual items comprising repair operations are
to be followed in the sequence in which they appear.
Items numbers in the illustration are referred to in the
text.
Adjustment and Repair operations include reference
to Service tool numbers and the associated
illustration depicts the tool in use. Adjustment and
repair operations also include reference to wear
limits, relevant data, torque figures, and specialist
information and useful assembly details. Each
adjustment or repair operation is given its Service
Repair Operation number.
WARNINGS, CAUTIONS and NOTES have the
following meanings:
WARNING: Procedures which must be followed
precisely to avoid the possibility of injury.
CAUTION: Calls attention to procedures which
must be followed to avoid damage to
components.
NOTE: Gives helpful information.References
References to the LH or RH side given in this Manual
are made when viewing the vehicle from the rear.
With the engine and gearbox assembly removed, the
crankshaft pulley end of the engine is referred to as
the front.
Operations covered in this Manual do not include
reference to testing the vehicle after repair. It is
essential that work is inspected and tested after
completion and if necessary a road test of the vehicle
is carried out particularly where safety related items
are concerned.
Dimensions
The dimensions quoted are to design engineering
specification with Service limits where applicable.

INTRODUCTION
01-4
λLambda
lc Low compression
LCD Liquid Crystal Display
LED Light Emitting Diode
LH Left-Hand
LHD Left-Hand Drive
LVS Liquid Vapour Separator
mMetre
µMicro
MAF Mass Air Flow
MAP Manifold Absolute Pressure
MFU Multi-Function Unit
MFL Multi-Function Logic
max. Maximum
MEMS Modular Engine Management
System
MIL Malfunction Indicator Lamp
min. Minimum
MPa MegaPascal
- Minus (tolerance)
' Minute (angle)
mm Millimetre
mph Miles per hour
MPi Multi-Point injection
MY Model Year
NAS North American Specification
(-) Negative (electrical)
Nm Newton metre
No. Number
NO
2Nitrogen Dioxide
NO
xOxides of Nitrogen
NTC Negative Temperature
Coefficient
OBD On Board Diagnostics
o.dia. Outside diameter
ORM Off-road Mode
ΩOhm
PAS Power Assisted Steering
PCV Positive Crankcase Ventilation
PDC Parking Distance Control
% Percentage
+ Plus (tolerance) or Positive
(electrical)
±Plus or minus (tolerance)
PTC Positive Temperature Coefficient
PTFE Polytetrafluorethylene
PWM Pulse Width Modulation
rRadius
:Ratio
ref Reference
RES Rover Engineering Standards
rev/min Revolutions per minute
RF Radio Frequency
RH Right-Hand
RHD Right-Hand Drive
ROM Read Only Memory
RON Research Octane Number
ROV Roll Over ValveROW Rest Of World
SAE Society of Automotive Engineers
" Second (angle)
SLABS Self Levelling and Anti-Lock
Brake System
SLS Self Levelling Suspension
SOHC Single Overhead Camshaft
sp.gr Specific gravity
SRS Supplementary Restraint System
std. Standard
synchro Synchronizer or synchromesh
TDC Top Dead Centre
TMAP Temperature, Manifold Absolute
Pressure
TP Throttle Position
TPS Throttle Position Sensor
TV Torsional Vibration
TXV Thermostatic Expansion Valve
UK United Kingdom
US United States
V Volt
Var. Variable
VIN Vehicle Identification Number
VIS Variable Intake System
VRS Variable Reluctance Sensor
VSS Vehicle Speed Signal
WWatt

GENERAL INFORMATION
03-2
Safety Instructions
Whenever possible, use a lift or pit when working
beneath vehicle, in preference to jacking. Chock
wheels as well as applying parking brake.
Jacking
Always use the recommended jacking points.
Always ensure that any lifting apparatus has
sufficient load capacity for the weight to be lifted.
Ensure the vehicle is standing on level ground prior
to lifting or jacking.
Apply the handbrake and chock the wheels.
WARNING: Do not work on or under a vehicle
supported only by a jack. Always support the
vehicle on safety stands.
Do not leave tools, lifting equipment, spilt oil, etc.
around or on the work bench area. Always keep a
clean and tidy work area.
Brake shoes and pads
Always fit the correct grade and specification of
brake linings. When renewing brake pads and brake
shoes, always replace as complete axle sets.Brake hydraulics
Observe the following recommendations when
working on the brake system:
lAlways use two spanners when loosening or
tightening brake pipe or hose connections.
lEnsure that hoses run in a natural curve and are
not kinked or twisted.
lFit brake pipes securely in their retaining clips
and ensure that the pipe cannot contact a
potential chafing point.
lContainers used for brake fluid must be kept
absolutely clean.
lDo not store brake fluid in an unsealed
container, it will absorb water and in this
condition would be dangerous to use due to a
lowering of its boiling point.
lDo not allow brake fluid to be contaminated with
mineral oil, or put new brake fluid in a container
which has previously contained mineral oil.
lDo not re-use brake fluid removed from the
system.
lAlways use clean brake fluid or a recommended
alternative to clean hydraulic components.
lAfter disconnection of brake pipes and hoses,
immediately fit suitable blanking caps or plugs to
prevent the ingress of dirt.
lOnly use the correct brake fittings with
compatible threads.
lObserve absolute cleanliness when working
with hydraulic components.
Cooling system caps and plugs
Extreme care is necessary when removing
expansion tank caps and coolant drain or bleed
screws when the engine is hot, especially if it is
overheated. To avoid the possibility of scalding,
allow the engine to cool before attempting removal.
Air suspension system
Whilst working on the air suspension system, eye
protection must be worn at all times.

GENERAL INFORMATION
03-27
Body Repairs
General
Body shells are of welded construction and bolted to
a chassis frame. Front and rear sections of the shell
are designed as 'energy absorbing' zones. This
means they are designed to deform progressively
when subjected to impact in order to minimise the
likelihood of injury to vehicle occupants.
It is essential that design dimensions and strength
are restored in accident rectification. It is important
that neither structural weakness nor excessive local
stiffness are introduced into the vehicle during body
repair.
Repairs usually involve a combination of operations
ranging from straightening procedures to renewal of
individual panels or panel assemblies. The repairer
will determine the repair method and this decision will
take into account a balance of economics between
labour and material costs and the availability of repair
facilities in both equipment and skills. It may also
involve considerations of the vehicles' downtime,
replacement vehicle availability and repair turn-
around time.
It is expected that a repairer will select the best and
most economic repair method possible, making use
of the facilities available. The instructions given are
intended to assist a skilled body repairer by
expanding approved procedures for panel
replacement. The objective is to restore the vehicle
to a safe running condition by carrying out a repair
which is as close as is feasible to original standard.
The results should not advertise to the experienced
eye that the vehicle has been damaged, although the
repair might not be identical in all respects to the
original factory build. Commercial bodyshop repair
facilities cannot always duplicate methods of
construction used during production.
Operations covered in this Manual do not include
reference to testing the vehicle after repair. It is
essential that work is inspected and suspension
geometry checked after completion. Where
necessary a road test of the vehicle should be carried
out, particularly where safety-related items are
concerned.
Where major units have been disconnected or
removed it is necessary to ensure that fluid levels are
checked and topped up where necessary. It is also
necessary to ensure that the repaired vehicle is in a
roadworthy condition in respect of tyre pressures,
lights, washer fluid etc. Body repairs often involve the removal of mechanical
and electrical units and associated wiring. Where
necessary, refer to the relevant section of the
Workshop Manual for removal and refitting
instructions.
Taking into consideration the differences in body
styles, suspension systems and engine and
transmission layouts, the location of the following
components as applicable to a particular vehicle is
critical:
lFront suspension upper damper mountings on
RH and LH chassis longitudinals.
lFront suspension or sub frame mountings.
lEngine mountings on RH and LH chassis
longitudinals.
lRear suspension upper damper mountings on
RH and LH chassis longitudinals.
lRear suspension mountings or lower pivots.
Additional points which can be used to check
alignment and assembly are:
lInner holes in cross member - side - main floor.
lHoles in front bulkhead.
lHoles in rear longitudinals.
lHoles in rear lower panels.
Apertures for windscreen, rear screen, bonnet and
doors can be measured and checked using the
dimensional information provided and also by
offering up an undamaged component as a gauge.
Straightening
Whenever possible, structural members should be
cold straightened under tension. Do not attempt to
straighten with a single pull but rework the damaged
area using a series of pulls, releasing tension
between each stage and using the opportunity to
check alignment.
Body jig
Unless damage is limited to cosmetic panels, all
repair work to body members must be carried out on
a body jig, to ensure that impact damage has not
spread into more remote parts of the structure.
Mounting on a jig will also ensure that the
straightening and panel replacement procedures do
not cause further distortion.
If original dimensions cannot be satisfactorily
restored by these methods, damaged structural
members should be replaced. Damaged areas
should be cut away using a high speed saw, NOT an
oxy-acetylene torch.
As a rule, body dimensions are symmetrical about
the centre line. A good initial check for distortion is
therefore to measure diagonally and to investigate
apparent differences in dimensions.