Land Rover Discovery: Manual Transmission - Transaxle
/ Diagnosis and Testing
PRINCIPLES OF OPERATION
For a detailed description of the Manual Transmission, refer to the relevant
Description and Operation section in the workshop manual. REFER to:
Manual Transmission (308-03 Manual Transmission/Transaxle, Description
and Operation).
INSPECTION AND VERIFICATION
CAUTION:
Diagnosis by substitution from a donor vehicle is NOT acceptable.
Substitution of control modules does not guarantee confirmation of a
fault, and may also cause additional faults in the vehicle being tested
and/or the donor vehicle.
NOTES:
- If a control module or a component is suspect and the vehicle
remains under manufacturer warranty, refer to the Warranty Policy
and Procedures manual, or determine if any prior approval
programme is in operation, prior to the installation of a new
module/component.
- When performing voltage or resistance tests, always use a digital
multimeter accurate to three decimal places, and with an up-todate
calibration certificate. When testing resistance always take the
resistance of the digital multimeter leads into account.
- Check and rectify basic faults before beginning diagnostic routines
involving pinpoint tests.
- Verify the customer concern
- Visually inspect for obvious signs of damage and system integrity
Visual Inspection
- If an obvious cause for an observed or reported concern is found,
correct the cause (if possible) before proceeding to the next step
- If the cause is not visually evident, verify the symptom and refer to
the
Symptom Chart, alternatively check for Diagnostic Trouble Codes
(DTCs) and refer to the DTC Index
- Check DDW for open campaigns. Refer to the corresponding bulletins
and SSMs which may be valid for the specific customer complaint and
carry out the recommendations as required
SYMPTOM CHART
NOTE:
Check the transmission fluid level prior to performing any further
diagnosis.
SYMPTOM:
Synchronizer crashing
or significant effort
required when
downshifting
POSSIBLE CAUSES:
- Gearshift
mechanism internal
failure
- Gearshift cables
incorrectly installed
- Manual transmission
internal failure
ACTION:
- Check the integrity of the gearshift
mechanism
- Check the installation of the gearshift
cables
- Install a new manual transmission
SYMPTOM:
Gear jumps out of
engagement while
driving
POSSIBLE CAUSES:
- Manual transmission
internal failure
ACTION:
- Install a new manual transmission
SYMPTOM:
Gearshift linkage
does not operate
freely (stiff or partially
seized)
POSSIBLE CAUSES:
- Gearshift
mechanism internal
failure
- Gearshift cables
incorrectly installed
- Manual transmission
internal failure
ACTION:
- Check the integrity of the gearshift
mechanism
- Check the installation of the gearshift
cables
- Install a new manual transmission
SYMPTOM:
Brief scratching noise
during gear shifting
POSSIBLE CAUSES:
- Manual transmission
internal failure
ACTION:
- Install a new manual transmission
SYMPTOM:
Fluid leak from the
manual transmission housing
POSSIBLE CAUSES:
- Fluid filler plug not
sealing
- Fluid drain plug not
sealing
- Input shaft oil seal
leaking
- Output shaft oil
seal(s) leaking
- Selector shaft oil
seal leaking
- Crankshaft rear seal
leaking
- Clutch slave cylinder
leaking
ACTION:
- Remove the fluid filler plug. Install a
new sealing washer. Install the filler plug and tighten to the specified
torque
- Remove the fluid drain plug. Install a
new sealing washer. Install the drain
plug and tighten to the specified
torque
- Install a new input shaft oil seal
- Install a new output shaft oil seal as
necessary
- Install a new crankshaft real oil seal
- Install a new clutch slave cylinder
SYMPTOM:
Clicking noises in
reverse gear
POSSIBLE CAUSES:
- Manual transmission
internal failure
ACTION:
- Install a new manual transmission
SYMPTOM:
Gear wheels banging
when shifting
POSSIBLE CAUSES:
- Manual transmission
fluid level low
- Clutch not
disengaging
completely when
the clutch pedal is
depressed
- Manual transmission
internal failure
ACTION:
- Refer to the relevant section of the
workshop manual and check the
manual transmission fluid level. Top
up as necessary
- Refer to the relevant section of the
workshop manual and check the
clutch system
- Install a new manual transmission
SYMPTOM:
Noises in the forward
gears
POSSIBLE CAUSES:
- Manual transmission
fluid level low
- Foul condition -
Engine/transmission
fouling body
- Engine/transmission
flange bolts loose
- Manual transmission
internal failure
ACTION:
- Refer to the relevant section of the
workshop manual and check the
manual transmission fluid level. Top
up as necessary
- Check the integrity of the
engine/transmission mountings
- Check the integrity of the
engine/transmission flange bolts
- Install a new manual transmission
SYMPTOM:
Gears jump out of
engagement
POSSIBLE CAUSES:
- Gearshift
mechanism internal
failure
- Gearshift cables
incorrectly installed
- Manual transmission
internal failure
ACTION:
- Check the integrity of the gearshift
mechanism
- Check the installation of the gearshift
cables
- Install a new manual transmission
SYMPTOM:
One of the gears
(particularly reverse)
cannot be selected
POSSIBLE CAUSES:
- Gearshift
mechanism internal
failure
- Gearshift cables
incorrectly installed
- Manual transmission
internal failure
ACTION:
- Check the integrity of the gearshift
mechanism
- Check the installation of the gearshift
cables
- Install a new manual transmission
SYMPTOM:
Unable to select first
and second gears
(third, sixth and
reverse ok)
POSSIBLE CAUSES:
- Gearshift
mechanism internal
failure - Broken
selector pin in gate
guide
- Gearshift cables
incorrectly installed
- Manual transmission
internal failure
ACTION:
NOTE:
DO NOT install a new manual
transmission for this fault.
- Install a new gearshift mechan
SYMPTOM:
Gearshift linkage has
excessive play
POSSIBLE CAUSES:
- Gearshift
mechanism internal
failure
- Gearshift cables
incorrectly installed
ACTION:
- Check the integrity of the gearshift
mechanism
- Check the installation of the gearshift
cables
SYMPTOM:
Clutch slipping
POSSIBLE CAUSES:
- Clutch pedal not
returning fully
- Clutch controls
hydraulic fault -
- Fluid leak, air
ingress, etc
- Clutch slave cylinder
not returning fully
- Clutch friction plate
excessively worn
- Clutch friction plate
contaminated with
oil
- Clutch friction plate
overheated
- Clutch pressure
plate warped/failed
ACTION:
SYMPTOM:
Clutch chatter or
shudder
POSSIBLE CAUSES:
- Engine/transmission
mountings
loose/damaged
- Clutch friction plate
contaminated with
oil
- Clutch pressure
plate warped/failed
- Dual mass flywheel
failure
ACTION:
SYMPTOM:
Clutch drag (difficulty
shifting)
POSSIBLE CAUSES:
- Clutch controls
hydraulic fault -
Fluid leak, air
ingress, etc
- Clutch not
disengaging
completely when
the clutch pedal is
depressed
- Clutch pressure
plate warped/failed
- Clutch friction plate
contaminated with
oil
- Clutch friction plate
not sliding freely on
the input shaft
splines
ACTION:
SYMPTOM:
Clutch pedal
pulsation
POSSIBLE CAUSES:
- Clutch/brake pedal
pivot shaft not
adequately
lubricated
- Clutch pressure
plate warped/failed
- Clutch release
bearing worn/failed
- Dual mass flywheel
failure
ACTION:
- Lubricate the clutch/brake pedal
pivot shaft
- Install a new clutch assembly
- Install a new clutch slave cylinder
- Install a new dual mass flywheel
DTC INDEX
For a list of Diagnostic Trouble Codes (DTCs) that could be logged on this
vehicle, please refer to Section 100-00.
READ NEXT:
REMOVAL
NOTES:
Removal steps in this procedure may contain installation details.
Some variation in the illustrations may occur, but the essential
information is always correct.
Refer to: Air Clea
REMOVAL
NOTES:
Removal steps in this procedure may contain installation details.
Some variation in the illustrations may occur, but the essential
information is always correct.
NOTE:
Neutral must
REMOVAL
NOTES:
Removal steps in this procedure may contain installation details.
Some variation in the illustrations may occur, but the essential
information is always correct.
CAUTION:
Make sure
SEE MORE:
PART(S)
REMOVAL
NOTES:
Removal steps in this procedure may contain installation details.
Using a suitable tool, release the trim panel..
Discard the retaining clips.
Disconnect the battery ground cable.
Refer to: Specifications (414-01 Battery, Mounting and Cables,
Specifications).
Open rea
REMOVAL
NOTE:
The rear side member lower side extension is installed in conjunction
with:
Rear bumper cover
Rear bumper
Back panel outer
Back panel inner
Rear lamp panel outer
The rear side member lower side extension is serviced as indicated.
Before commencing this procedure make sure t