Quote: How are you sintalling teh u joints? Are you seating them against the clips after installing the clips? It's driveshaft. Definately. If you moved it up and fdowna couple degrees (pinion angle) what is is currently set at? You are positive you're measuring it properly?
im using a vise to put them in and pushing them up against the clips too.
There are 4 clips to align the u joint 2 that retain the joint in the shaft.
And 2 that position the joint in the pinion yoke. Some people discard these, do you still have yours? They are needed as they properly position/align the joint into the pinion yoke.
You also stated you did Not replace the crush sleeve when you did the gear change. If you grab the pinion yoke can you force any up or down play out of it, or is it tight.
On the front yoke you stated you had plenty of clearence. How much is plenty, if you have to much that can cause vibration too. After bottoming out the slip yoke I like about 1/2 to 3/4 of a inch clearence. 1" would be max IMO
Also what happend with you putting that thing on stands and running with no shaft and a slip yoke plug. On sunday you said that was a great idea and would try that.
But today you take it out for another cruise only to confirm the vibration, again!!
I too think its related to the shaft or its componets. When you did the shaft run out was it installed on the car or on v blocks.
You will get her figured out, because you have alot heads working on it . mike
i do have the clips in the ujoint all the way around, i have a max of 3/4 clearance, i didnt get a chance to spin it on the stands with just the yoke in the tail shaft cause i had to work. im gonna do my best to try it tomorrow after work, cause friday,sat and sun i'll be camping in the pocono's lol
. mike 
