I'm still in the process of figuring out this vibration.
It happens between 60 and 70 mph, when truck is in overdrive, but with 4.10 gears that's the only way I can go that fast. Both u joints in the shaft are brand new, it sounds like a u joint binding though. I had a second person shift between park and neutral and watched everything. There's was a little movement in the tranny mount , so I replaced that, no change( except that now my engine vibrates the truck like crazy at idle in gear). I watched the pinion move quite a bit as the truck was shifted between drive and reverse. I checked the pinion for any play in the bearings and it seems tight, as does the output of the transfer case. The only thing I can see is that it's time to replace the leaf springs. Truck is a 1993 regular cab 3/4 4x4 automatic. Any insight would be greatly appreciated.

 

Bent rim?

 

Does it stop doing it if you punch the button and drop out of OD?

I'm assuming you've had the tire balance checked out?

 

carrier bearing? i had a 03 that did the same thing changed it and all was well.

 

I checked it tonight, the vibration seems to be in every gear, but gets progressively worse, it gets worse on decelleration, but is still present on acceleration

 

I'm thinking you need to get your wheels balanced, or is it not that kind of vibration? Do you feel it from the steering wheel, or the whole truck? I had a right front tire out a few years ago, and the whole truck shook.

 

I think I narrowed it down to a vibration in the rear end, seems like a bad bearing! How hard is it to replace a carrier bearing, as im pretty sure its not the pinion bearing

 

You could pull the axle shafts and the rear drive shaft and drive as a front wheel drive to confirm that the problem is in the rear.

JP.

 

Check the pinion gear. When my Dana 70 went I had no vibration in 1st and 2ND, when I got to 3rd is when the vibration started and got worse in 4Th and 5Th. I thought it was the transmission but, when I took the rear cover off the chunks of pinion fell into my drain pan and the oil was metallic. It wiped out my RAWL sensor ring also.

 

This is multipul choice , i always start w/ the least costly and pay my up. In most cases it will be ypur last choise (lol). Mine was carrier bearing,and bent frnt., rim. good luck anyway.

 

Update,
I opened the rear diff, a little pinion play, tightened it up until I can rebuild it, rebalanced the wheels and installed new shocks.
Tightening the pinion helped with the clunking while changing gears.
Rebalancing the wheels had a significant effect, had them balanced by a truck shop on a static balancer, huge improvement.
New shocks substantially improved the ride and tamed the bumps significantly.
I still have a bearing noise between 60 and 70 mph, it's either the pinion bearings, or something in the transfer case

 

Just thought I'd update.
Turned out to be a series of issues
Wheels out of balance, rebalancing made a bunch of vibrations go away,
Balanced driveshaft, huge difference, especially in the 60 to 70 mph range
There's still slop in the pinion, and a little in the transfer case output, as well as a worn out slip joint in the front shaft. Combined with the fact that my kingpins need some attention, I got most of it out,