Nothing personal, but I am not sold on a hub based on when it occurs, what gear or if neutral.
Look forward in hearing the fix

 

That's a great tip. I just googled it and the price variance is... SHOCKING.

 

Mike, I'm looking forward to a fix too!!!!
I'm pretty sure it isn't a bearing, the good Dr is bang on with the symptoms I am experiencing but I have replaced too many bearings over the years to think it is one, especially since it doesn't vibrate when the drive shaft is out....
No idea moving forward. I'll go back to this post down the road when it gets sorted out.
Dr..... If it turns out to be a bearing then you called it.

 

Has this problem ever been solved?
I have exactly the same problem and replaced almost everything. Don’t know what to do anymore.

 

It will help us if you could be more specific about what you had replaced.... as well as more info about your truck set up, e.g., lifted or not lifted?

 

Take the driveshaft to a shop and have it balanced, or at least checked.

 

I replaced the following on my Disco 2 V8 2001:
front and rear propshaft incl balancing
rear rubber coupling
transfercase
all 4 wheel bearing hubs
wheels are 3 times rebalanced
watts linkage, all original bushings
radius arm bushings
ball joints
ace bushings and rubbers

Runs very fine until 118kmh from then I starts to vibrate throughout the car, not the steering wheel.
the peak is at 120kmh but still noticeable at higher speeds.

Car is not lifted

vibration is speed related, even when I put it in neutral it still vibrates. Also feel no vibration when braking at that speeds.

 

Do you feel the vibration in the steering wheel or in the seat... Or both?

 

I faced a similar predicament, rotational vibration at 50 to 60 mph. Lifted two inches. New coils and shock absorbers, new watts, new T/C, new driveshafts re-balanced, new steering and suspension poly bushes, new diff. Tires were BFG K02s which were about 2 years old. Wheels/tires had been checked and re-balanced a number of times. Vibration still persisted. We decided to try with another set of similar factory wheels and tires. Vibration went away.

I ended up taking my tires/wheels to a shop who offers Round Force balancing. RoadForce balancing for the 4 wheels ran CAN$180 (around US$150). Turns out one of the KO2s were so out of round for some reason. Replacing this one errant tire fixed the vibration issue.

One suggestion is to rotate the wheels, go for a drive and see if the main vibration central point has changed. This a cheap preliminary way to deduce if the wheels/tires may be an issue.

All the best with finding the fix. Hope this helps.

 

I suspected the Wheels as well. So I tried 3 different sets of them. All on factory rims. The vibration keeps exactly the same.
Only difference is when I try a larger tyre the vibration gets worse and then shifts to 128kmh. (Larger diameter)