I've an annoying oil leak on my late model TD5 Disco. Having gunked the underneath the only drips I can find are on the bottom two bolts that connect the gearbox bell housing to the engine block. I'm guessing from this, the leak is probably the rear crankshaft seal, although, I'm open to suggestions.

Between the bottom two bolts there appears to be some sort of drain plug - what's this for, I cannot find any reference to this in the Rave manual. If I remove this what's likely to happen, I'm wondering if there's some oil floating around in the bell housing, although clutch is working fine.

Any advice will be appreciated, cheers