T5 trans swap question

[dhamilton62]

Originally Posted by CRGRS 66

If your drive shaft U joints are not new, you may want to start there. Is your truck lowered? Pinion angle may be the issue as it is only at highway speeds. Drive shaft out of balance could be an issue, did you shorten it yourself, or have it done at a shop?

Thanks so much for all the great help and input from everyone! I have brand new u-joints in the truck after I had it shortened by a great shop that only deals with drivelines. The truck is lowered from the previous owner at about a 5" drop. Is there a fix for the pinion angle? I ran through the trans before I put it in. All new syncros, and bearings so I can't imagine its the trans as I still don't have a floor pan in the truck so I can hear and feel the trans driving around and it feels and sounds good at 60 to 65 but after that things get a little shaky, especially when a load isn't on the truck. The rear end is the old HO32 which I want to swap to a 12 bolt. Could the rear end cause that? Or even the motor mounts since I'm still using the old horseshoe mount? I really appreciate everyones help, and hopefully I can get it all sorted out!