Driveline problems

[Tim Buja <buja@domain.elided>]

Now that I've got just over 1000 miles on my Stag after a 20 month total
engine rebuild, I'm finding some problems that I forgot about since it
was last running in 1996.

Specifically, there is a very noticable whine from under the back seat
under part throttle between ~50 and ~58mph.  The frequency of the whine
is dependent on road speed, and the volume is dependent on throttle
position.  Maintaining a steady speed of 55mph is very aggravating due
to the whine.  If I power through this speed range to above 60 mph, the
whine is considerably less noticable than when I maintain a steady 55mph.
Coasting down from 60 to 50 is totally quiet.  BTW, the tach reading
at the peak whine volume is around 3200 rpm.  The noise is a whine,
and not a rumble typically associated with failing wheel bearings.

I'm in the process of lowering the differential casing and removing the
pinion extension housing to examine the quill shaft bearing.  I have a
new bearing ready for installation.  The differential was checked in 1996
and I was told that the gear wear looked normal.  Does anyone have any
hints on what I should look for when I get everything out?

One more thing - when I took the halfshafts off, I noticed that the
flange and shaft on the left side of the differential had about 3/16"
end float, while the other side had almost none.  To me, this doesn't
seem quite right, but I haven't had a chance to find the details in
the ROM yet.  All three differential bearings "felt" OK when I rotated
each shaft.  Any hints?

Thanks in advance,
Tim Buja - Rockford, Illinois, USA - 80 TR8, 73 Stag, 72 TR6