Salisbury Diff Pinion Seal Installation

[keynsham]

I recently replaced the pinion seal in my 350 and it almost immediately leaked again. I have removed it and it would seem the oil was leaking not from the rubber seal, but around the outer edger of the seal where it is pressed into the diff housing! It had been installed correctly so I am not sure why this hsould be possible. I plan to replace it with a new seal and install it with a layer of gasket sealer such as red hermatite.

Is this a common problem as I have never needed to fit a seal in this way before?

[madformotors]

I see on an exploded diagram of a Scimitar (Salisbury) axle there's a gasket fitted behind the pinion oil seal. Ive always changed the oil seal and never bothered with a gasket, but i can see the potential for oil sneaking past the outside of the seal rather than past the rubber (or leather) part. Maybe make a gasket for behind the seal using it as a template? Thinking back though iirc i probably used a smear of hermetite.