I got the rear of the car up on jacks and had a buddy sit in the driver's with the car in Drive so I could watch the drive shaft spin while I looked for eccentric or wobbling action at the universals and the support bearing. It all spun perfectly. No visible anomalies. (This perfect spin might not be that way if the wheels were on the ground) But when I had him gun the engine a bit, the transaxle LIFTED and TURNED a bit. I was astounded. I thought the transaxle was fixed in place. There are the two rods that keep the transaxle in place - but they have rubber bushings that bolts go through. Is it the worn bushings that are allowing the transaxle to turn on it's axis? Could THIS be the source of the vibration?
The rear of the tranny is leaking and this could be from that vertical motion. The centering bushing I am told is inside the end of the tranny - or IS he end of the tranny - could be worn from this motion or the oil seal there (is there is one?) could be warped because of this motion?
Is there someplace I could order Volvo bushings - or a pack of universal bushings that would fit? the stabilization bars or torque bars cost $140 - and I just need the bushings.