Gearbox Clutch CVs - Warnings

New owners - Check your gearbox oil level, whatever you have been told about previous servicing!

It has come to our notice over several years, that many gearbox problems and indeed, total gearbox failures are caused not by simple wear and tear, but by a simple lack of oil.

These vehicles are now old, and gearboxes can slowly leak oil. Very often this is because the castings (particularly early ones) corrode, and the sections ease apart, allowing slow but consistent weeping/leaking. THis can sometimes easily be fixed, but read on...

Many garages do not think about (nor are paid to) check the gearbox oil level. It is not a normal service item. It is not a 5 minute job, indeed, without draining and refilling, there is no easy way to accurately determine the actual level. It may be possible to estimate it without dropping and refreshing the oil. Even when a mechanic underneath spots a drip or weep of oil around a gearbox mating joint, they may well just wipe it off rather than realise it is a sympton that needs investigating further, due to poor vehicle specific knowledge, or common lack of the 'what if' mentality...

NB. Additionally, it is sometimes not too easy to remove the oil filler plug. Remember, do not remove the drain plug until the filler plug has been loosened

So, if you have just acquired a T25...

then it is a very good idea to get a garage or T25 savvy person to make sure your gearbox has actually got some oil in it.

T25 gearboxes are becoming expensive, some parts are now difficult or impossible to buy new, or are very expensive. A typical rebuild could cost from £750 to £1500, and requires specialist knowledge and tooling. Take care of yours, if in doubt, refresh the oil with the correct grade, and read the gearchanging hints & tips in other Gearbox Wiki topics, particularly those releavnt to very cold weather and/or bad linkages.

Recommendations for those few in the UK who can be relied upon to rebuild these boxes correctly, can be obtained by posting a question on the forum.

Aidan on driving technique to prolong life of box

Remember folks the steering wheel is where your hands should be except at the point of changing gear, don't drive with your hand on the gearstick (in any vehicle) as even the slightest pressure or movement can cause wear in parts that want to be in their natural resting place, eventually that wear can cause selection issues