Vibration at highway speeds (cont'd)

["Craig D. Niederst" <niederst@telerama.com>]

First of all, a big thank you to all who responded to my original question.
In a nutshell, occasionally at highway speeds (~80 mph), my '92 100S will
"shake" violently. This appears to be coming from the right front wheel of
the car. Applying the brakes stops the vibration immediately. It seems the
braking itself does not stop the vibration, but just the fact the car slows
down (but not 100% sure). So far I've ruled out an out of balance tire or an
out of round wheel (this vibration has occurred with both my snows and
summer wheels). A couple of Listers suggested a bad tie rod end. I jacked up
each front wheel tonight, and grabbed the wheel at 3 and 9 o'clock, and
tried to push and pull the wheel in or out. Both sides didn't budge at all,
so it looks like the tie rod ends are OK. With the wheels off, it looks like
all bushings, control arms, etc are in good shape, and all brake hardware is
tight and in good working order. So far, looked like a dead end. I
reinstalled the wheels, and while the cars was still in the air, I "punched"
each wheel at 3, 6, 9 and 12 o'clock. The left front wheel was solid when
punched at all four positions. But the right front wheel seemed to quiver a
bit when punched at the 3 and 9 o'clock positions (but was solid in the 6
and 12 o'clock positions). I know this is probably a piss poor test, but am
I onto something here? Any ideas what would cause this "quiver?" TIA.

Craig
'92 100S (80k)