Originally Posted by phil_focus

well thats definately the gearbox casings joint and if thats your car there is an oily residue on the subframe exactly where i'd expect for a leak in that area.

it might not be that join though it could be a leaky drive shaft seal where your passenger side drive shaft goes into the box. if it is then thats pretty easy to sort and diagnose.

i'll keep my fingers crossed for you.