I put another rear end in my truck after finding that I could move the pinion 1/4 inch up and down on the used one I just bought. After doing this and putting my 2 piece driveshaft back in with a 1 inch spacer under the carrier it has very little vibration again, maybe best I leave it alone and just drive it a for a while. I need to measure my pinion angle and my first drive shaft and make them the same but I am not going to right now. The frame dad put under his truck helped his vibration some although I believe his new driveshaft is not balanced correctly is why he still has some.