The Land Rover V-8 is capable of a long service life if properly maintained. What can kill them early? One major cause is overheating. This aluminum alloy engine is prone towards seeping from the head gaskets after getting too warm--too often. The "weep hole" under the snout of the water pump will show stains from  coolant escaping past the bearing and seal-- long before the steady dripping starts. Make sure the Viscous Fan Clutch is operating properly (Free-wheels when engine is cold--Engages to pull air through the Radiator when engine is warm- up to 3500rpm). This component frequently reaches the end of its service life when the water pump does. It can adversely affect gas mileage if locking up when the engine is at  temperature.

In the event your Land Rover does require the head gaskets being replaced due to a severe overheating event, there are a few potential problem areas to be aware of. The V-8 engine uses a steel cylinder liner pressed into the aluminum alloy Block. Make sure none of the liners have dropped below the deck surface as a result of the overheating. If this has occured, you are wasting your time machining the cylinder heads flat again and replacing gaskets. The Block must be replaced. We have also seen Blocks with internal cracks-- hidden from view-- that resulted in a engine that idled fine with normal temperature after a head gasket job, but quickly ran hot under load on the highway. Bottom line?-- if it pegged the gage while driving for any more than 5-10 minutes or was vacant of coolant when disassembled, the odds are you are looking at a Block replacement. This is why it is so important to maintain your cooling system on these vehicles.

Oil consumption between change intervals is a normal situation, so check the level every few tanks of fuel (we have seen vehicles come in 4 qts. low on oil ! ). Also be aware of the Oil Cooler hoses passing the stage of seepage and leaving tell-tale signs on the driveway. Cheap insurance to replace these and avoid a engine replacement costing many thousands of dollars.

The throttle body heater gasket/plate fails with some frequency-- with subsequent engine coolant loss. This again--can lead to overheating. The Viscous Fan Clutch and radiator hoses should always be replaced when replacing the water pump. And-- so should the Serpentine belt (or V-Belts on early engines). While you are in there, make sure the tensioner and idler pulley are in good shape (especially on the Discovery II model). No use tearing up a new belt. You might hear a whining noise or feel a vibration at idle that just wasn't there before, when these units are failing.

Check engine lights are frequently triggered by bad plug wires, coil pack or a Mass Flow meter. Be aware that on the later Discovery you must remove the upper plenum to change out the spark plug wires. We supply that plenum gasket with the wire set for this purpose.

The ZF transmission has shown few cases of premature failure if it is serviced properly. If you tow with your Land Rover service the transmission once a season. One area that requires monitoring is the transmission cooler lines. A little seepage is acceptable. But lose one, and that spells doom for the transmission. Check the connections at both ends and ALWAYS replace the O-rings when fitting new lines. Also be aware that on the 4.0/4.6 Range Rover, 50% of the time the fittings will be so difficult to remove that damage to the cooler may occur as a result of replacing them.

The transfer case can suffer a stretched chain (which requires the whole assy be removed and split apart). The input and output shafts have seals that need inspection and prompt replacement if they are leaking. The internal viscous unit has failed on some models. You can tell by driving in tight circles and listening for-- and feeling-- jerkiness in the vehicle. A failed viscous unit puts a lot of strain on the differentials, sometimes resulting in damage to the gears and bearings inside the two units. Check the front and rear driveshafts for failing universal joints (Carden joint on Disco II). We have seen a complete "exiting of the vehicle" on front driveshafts when they fail, and it wasn't pretty!

The front and rear differential fluid is something we change at every major service (every 30K miles). However-- a leaking axle seal-- which in the rear manifests itself with gear oil on the inside of the wheel and usually a soaked brake caliper, can compromise the health of this major component. Front axle seals that have failed end up allowing gear lube to enter the swivel-pin housings where it mixes with the grease. This can shorten the life of this component and you may see seepage around the swivel ball seals. On the Discovery watch the pinion seals. And take no chances with the Flex Disk on this model-- which joins the rear driveshaft to the differential. They are a normal replacement item, and when they are failing the vibration level at highway speeds gets your attention fast. Left unattended the pinion bearing and seal will also fail prematurely from the vibration beating these components up. On the Range Rover Classic and Disco I there is a flange kit to reduce vibration and offer better pinion bearing sealing on the rear differential. 

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