Workshop Manuals Factory service & repair Land Rover
01 Introduction02 General specification data03 Engine tuning data04 General fitting reminders05 Lubricants, fluids and capacities06 Maintenance07 Engine08 Emission control09 Fuel system10 Cooling system11 Manifold and exhaust system12 Transfer gearbox13 Automatic gearbox14 Propeller shafts15 Rear axle and final drive16 Front axle and final drive17 Steering18 Front suspension19 Rear suspension20 Brakes21 Wheels and tyres22 Chassis and body23 Heating and ventilation24 Air conditioning25 Wipers and washers26 Electrical27 Instruments
Land Rover Defender 90 Workshop Manual (NAS)12 · Transfer gearbox
12 · Transmission

OIL LEAKS Leak between main and transfer gearboxes.

Make
Land Rover
Model
Defender 90 Workshop Manual (NAS)
Section
Fault diagnosis › OIL LEAKS Leak between main and transfer gearboxes.
Transfer gearboxOIL LEAKS Leak between main and transfer gearboxes.

OIL LEAKS Leak between main and transfer gearboxes.

Verify that oil leak is from transfer box and not main gearbox before proceeding with checks.

Prior to road test

  1. Check oil level in transfer box is correct.
  2. Check tightness of level and drain plugs.
  3. Check breather system for blockage. To validate system pipe must be removed, inspected, rectified as necessary and refitted.
  4. Remove all traces of oil from exterior of transfer box.

Take vehicle for short road test.

  1. Identify source of leaks and rectify as follows.

Front or rear output seal leaking:-

  1. Drain oil and remove leaking output flange.
  2. Inspect seal track on flange for surface damage. If damaged renew component. not damaged when refitting transfer gearbox.
  3. Remove and discard oil seal.
  4. Inspect seal locating bore and remove any sharp 10. If red A.T.F type oil is seen leaking during edges which may damage new oil seal.
  5. Fit new seal.
  6. Fit output flange and all other parts.
  7. Add oil to correct level into gearbox. See Detent plug or electrical switch leaks. LUBRICANTS, FLUIDS AND CAPACITIES, Information, Recommended Lubricants and Fluids

Cover plate sealant leaking.

  1. Drain oil and remove leaking cover plate.
  2. Remove all traces of joint sealant from both joint faces.
  3. Degrease all components and apply a thin film of Hylomar sealant, to both joint faces.
  4. Apply thread sealant to bolts which come into contact with gearbox oil.
  5. Refit cover plate.

CAUTION: Care must be taken not to overtighten fixings.

  1. Site vehicle onto a ramp [hoist].
  2. Select neutral in transfer box and select 4th gear in main gearbox.
  3. Run engine at 2000 rpm with clutch/drive engaged.
  4. Observe joint between main and transfer boxes.
  5. If oil leak is found establish if it is gear oil.
  6. If so, leak is originating from transfer box.
  7. Check two inner (main/transfer) bolts are oil tight, as these holes are tapped into the main transfer case.
  8. Remove transfer box to inspect mainshaft collar seal track condition, and front face of transfer case for porosity. See Repair, LT230Q Transfer Gearbox
  9. If these areas require servicing, transfer gearbox input seal must also be renewed.
  • CAUTION: Avoid damaging new seal lip
  • and ensure seal is fitted flush with
  • machined face. Also ensure new seal is

workshop test, investigate main gearbox for cause of leak.

  1. Detent plugs and electrical switches do not usually leak. It must be noted that they fit into open tapped holes in transfer case and therefore should be considered when looking for source of leak.

Parts & tools for this job For Land Rover Defender

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