Diff oil leak

[Mike Wattam <101714.1343@domain.elided>]

You don't say which type of oil seal you have fitted.  If it was the
original type leather seal, then it is likely to leak until it absorbs oil
and contracts over the shaft.  If the modern lip type oil seal, there must
be a problem.

The oil seal running surface on the quill shaft is fairly insensitive to
grooving, but the seal itself can be damaged on refitting the diff.  It is
all too easy to let the weight of the diff be taken on the seal during
fitting when the quill shaft and sub-frame is left in the car.  Mainly for
this reason, I would advocate dropping the whole subframe assembly (sounds
easy, apart from the weight it is) and then it can be offered up nicely
without any strains or possible dirt ingress.

As far as I am aware, there is only one supplier who supplies the absolute
correct size oil seal, and that is Tony Hart (as in many other things).  I
have no financial connection with Tony Hart.

I am assuming you also changed the quill shaft bearing.  If you did not,
this will be badly worn, and now running without oil (it was prepacked with
grease but the leaking oil seal would have washed this out!).

As regards the correct oil, if you use too heavy a grade the synchro
becomes a bit of a pest.  I would however use straight 80 grade as the
lightest available, and this works OK.

Mike Wattam
Triumph Stag Register