I've posted numerous times on this but here's the latest:
Heavy oscillating drone starts at 40 mph and gets worse with drive time and speed.
What I've checked:
Tires & Wheels: Drove with different sets, still vibrating
Front axle: Remove shafts, replaced unit bearings, still vibrating even with shafts out
Steering components: Alignment is spot on, track bar is correct length and orientation to drag link is correct. U joints are fine.
Removed front drive shaft and drove...still vibrating, same with rear and driving in 4 hi
Rear axle: replaced housing, took out bad spider gears, had locker and new gears/bearings and axle shafts installed. Vibe present before and after.
All suspension components bolted on tight, LCAs are correct length. (Rock Krawler).

I'm exhausted. This thing vibrates really bad and only has 24000 miles on it.

 

Auto or stick

 

Automatic, 4 Door, 2.5" RK Max Travel

 

What's the dealership said? Is it not covered under warranty? Or have your mods voided it?

 

If dealership voids go to a local off road shop and see of they have any clue might of some help

 

Explain a little more about your symptoms. Is this while accelerating? Is this while coasting?

 

Recheck your control arms. I have the same lift. When we installed it, it drove dead straight with no vibrations. After I took it for an alignment, it developed a vibration. Turns out the shop readjusted the control arms and put them back to stock specs. I took it back and got them to set the control arms back to the correct length. Vibration vanished. If you didn't specifically tell them NOT to adjust the control arms, they probly did.

 

Years ago I had a similar problem on my 1998 XJ. The problem was resolved when a very knowledgeable shop owner (Jeff Sugg @ MIT) recommended checking the front carrier bearings. He discovered the carrier bearing races were pitted due to poor quality materials...
Once the carrier bearings and races were replaced; the droning sound was gone....

 

Front driveline? Take it off and drive around.

 

seems like youve checked everything but the ball joints. They will give you some troublesome vibes in all circumstances