any other suggestions?

 

Let's start over from the beginning. You said the truck has 16,000 miles.

Does it still have the original tires?

How often are they rotated?

Have they ever been balanced aside from the factory?

Lucas

 

Definately not the wheels or tires...I have changed them and the vibration is still there

 

So what was the deal with the axle? You said you had it pulled and faced off. Why did that happen?

Lucas

 

It had a slight tweak in the end (someone must have hit a curb or pothole)
So I had it straightened and we faced the end to get it pretty much perfect. It still has a very little bit of runout once you look at it running with 22" wheels but not enough to get this damn vibration. What is frustrating about the vibration is it isnt constant and sometimes worse then other times

 

If your axles aren't perfectly straight and true, I'd be betting on that then. You haven't lowered or lifted the truck have you?

 

I have lowered it 1" in the rear with shackles but it still had still problem prior.
The axles probably have a very small amount of run out from new which is multiplied by the time it gets to the outside of a 22" wheel. I only have about 3 thou at the axle face. Maybe these things are super sensitive because I have seen wrose with no vibration. It still doesnt make sense on why it is worse at other times. Maybe I take it to a rearend shop and see what they I think as I am over it

 

With really big tires and wheels, it will be more sensitive. Acceptable runout is usually .1mm or less. That's pretty dang small. How are the ujoints on the driveshaft, and the pinion bearing on the rear diff?

 

Mayb check the limited slip? I have the same prob an I've checked most things an I was thinkin either shocks,leaf springs gone in the rear end. I had a friend follow me at 55 an he said the bed was bouncing an wobbleing a lot.
U may want to try an get a friend to follow u at the mph its the worst at. Hope this helps.

 

I checked the shocks and they seem ok. they are Bilsteins. I will need to take a good look at the pinion bearings and LSD. The tray bounces around side to side like you said when it is happening....quite noticable.