So there is a vibration whe we hit a certain speed and hold it there.  We can feel it build up to a point when its vibrating and you can feel the car shake. (strong words we know).  We hoped like $%^ that it was a universal joint and with a small amount of money and a bit of time we could fix it.  To this end we cracked open the shop manual and discovered there are 2 drive shafts. (what the...)  Now this next part sounds like we are making this up but the manual calls them "Propeller Shafts". (insert boat joke here)

Naturally the front, of the front, shaft (lets just call this the short shaft) mates to the transmission via a spline:
ShaftTransSpline

Seems normal and completely reasonable.  Here is another view with the transmission out of the way:
ShaftTransSpline2

You can see, off in the distance, where the short shaft (actual name is Front Shaft per the manual) rides in the center carrier bearing.  Here is a closer look:
ShaftCenterCarrier

The cross member has a large hole in the front side and a second cross member houses the center carrier.  note: the spring in the foreground isthe emergency brake spring.

Once we got both shafts and the center carrier out we layed them out on the bench and started replacing bits.
ShaftsOnBench

From left to right we replaced the following:

  • Universal joint to the differential
  • Universal joint to the center carrier bearing spline
  • Center Carrier Bearing (actually shown in lower left with new bearing)
    • We had to take the part to a shop to have the bearing pressed out and the new on inserted
  • Center Carrier grommets (shown near the channel lock jaws)  These isolate the carrier from the cross member
  • Univeral joint to the transmission spline

To remove the universal joints we rented a tool from O' Reilleys which made the job much easier.  Not exactly easy but easier.  Did it removed the vibration?  No!  It did not make it worse but we felt it did nothing to relieve the issue.  Was it needed, most likely not.  Was it a complete fail, not really as it again did not make it worse and could be considered preventitive maintenance...