5kTQw vibration under load

[Robert Deis]

Hey, all.  Just added a very pretty 87 5kTQw to my stable (kudos to Chris
at Force5 again, nice to do business with him). It's much better looking
and faster than the my 86, but has a few issues of its own. To whit:

The car has a very strong vibration under load.  Vibration seems to be
located beneath and just forward of the driver's footwell, almost as if
the diveshaft there was about to jump off.

Vibration frequency is speed-dependent, but severity is load dependent. If
I drive gently it is barely noticable or nonexistant, but at 1.0-1.1+ bar
it becomes very severe.

I looked around under the car yesterday and couldn't find anything
obviously loose or rubbing, all CV boots appear in tact.

The shocks are shot, but the mounts and bushings haven't obviously failed.
(Some wear is evident, but nothing's loose)

I only found two things amiss, I'm not sure if they could be related or
not:

1: There is a stripe of thrown grease/oil on the body near where the
propellor shaft goes in to the rear of the transmission. This might point
to a failing CV on the front of the propellor shaft, but the boot
is in tack and the vibration feels like its coming from farther forward
and left of there....

2: Carrier bearing on the propellor shaft seems to allow more movement
than the one on the '86. I don't know how much is too much?

Any ideas?
--
------------------------------------------------------------------------------
  Rob Deis                  "Let the people know beforehand what the law
  MiB3347                      is and what they are to expect."
  rdeis at io.com                              -- 18th Congress, Rec. 75