Is the car lowered? If it is, then the driveshaft length will have been shortened and the compression may be causing the grease to spew out.
If not, it may have a split in the boot or the band may be loose.
I think it's a H4 globe which is dual filament. It has a low and a high beam filament in it along with a separate single filament globe (H7 from memory) for the actual high beam.
I would pull the globe and check visually, then swap to the other side.
I have two suggestions...
1. Burn the car to the ground.
2. Remove the cabin filter(behind the glovebox) and spray bug spray down the air intake cowl at the rear of the bonnet with the fan running.
I would advise you do a bit of reading in the pinned RAV4 diesel post.
http://au.toyotaownersclub.com/forums/topic/37242-rav4-2ad-ftv-turbo-diesel-excessive-oil-consumption/