We had a customer in the shop today who had a problem with the gear change with their 1997 Land Rover Discovery 1 300TDi, not an uncommon complaint as the gearboxes can be notchy but on this one the gearstick was very stiff and very hard to engage any gear.
It was difficult to diagnose the problem, the clutch felt fine, not too hard and the biting point felt good. Talking to the customer it became apparent that the Discovery had recently been to a garage and had a thorough service including changing the gearbox fluid. The customer said the garage knew what they were doing and used EP90/90 gear oil in the axles and the main and transfer gearboxes! Ooops!
We have come across this several times, you could be forgiven for thinking a gearbox should have gear oil but it is not correct for the Land Rover R380 gearbox. Gear oil is too thick and will make gear changes nearly impossible.
The correct oil is Land Rover’s MTF94 which is a straw coloured thin fluid with special additives. There are also some aftermarket brands such as Comma Oil’s MVMTF 75W-80 that are suitable. If you cannot get the correct fluid you could at a push use regular automatic transmission fluid (ATF) which is again a thin fluid with a deep red colour.
The gearbox capacity is 2.4 litres, it is worth checking your fluid to see if you have the correct grade of gearbox fluid. This is an easy DIY job that can be done at home on the floor. EP80/90 and ATF both have their own distinctive smells so it is easy to tell which you have, just undo the filler plug and have a sniff!
Our customer phone us back later to say he drained the gearbox and it was gear oil, he refilled with MTF94 and the gear change has improved, we advised to run it for a few days and then drain and refill again to make sure all the gear oil is flushed out.
Changing the gearbox fluid to the correct fluid will make the gear changes better, these gearboxes are well known for their notchiness so don’t expect a silky smooth gear box!