Did you feel any play in the output flange without removing the driveshaft?

I may well end up removing the shaft, but I'm dreading it because it's fused to that output flange (use release paste, kids).

 

Nope, the only way i found out it was the problem what i put my disco on a lift then locked the t-case and pulled the abs fuse.locking the t-case makes it so the front and rear drive shaft get 50/50 power, and pulling the abs fuse make it so the traction control doesn't freak out. This my thread on the issue with vids https://landroverforums.com/forum/di...bration-78727/

 

Very interesting. I'm now seriously considering mounting an old phone or other camera to the underbody to get a video of it while it's going.

 

I tried adding more weights on the shaft, but it's not having any effect on the vibration. I found an old point-and-shoot, and I'm going to try duct-taping it up there and recording. Perhaps this will reveal something useful.

 

I'm going to take some video of this thing in action on Friday when I have free time during daylight hours, but I was tooling around underneath today and noticed that there's a slight play in the front shaft in some positions but not in others (I was moving the car back and forth a few meters and checking the shaft). Is this an indication of anything?

 

I had the exact issue and replaced the rear shaft which totally fixed the problem. I considered replacing the joints, but with parts and labor it was way easier and more cost effective to replace the entire shaft. No vibration since.

'04, Disco 2, HSE 7, 115k at the time I replaced the shaft.

 

It might also be the rotoflex coupling on the rear drive shaft.I also had that go out on me causing vibrations:

 

That's interesting -- I haven't looked much at the rear shaft, but I just replaced the rear diff, which was heavily worn. Perhaps there's some relationship. The rotoflex thing looks fine. Maybe this is something to investigate. I'm hoping my camera experiments will give some clues.

 

I had a look at the rear shaft and it looks fine, at least visually. I did notice there was an almost imperceptible wobble at the UJ closest to the parking brake. Basically if I try to move the shaft along one axis of the UJ, it will move a very slight amount—so slight that you have to strain to see it at the joint but can definitely feel it. It doesn't move at all along the other axis of the UJ.

This seems like an unlikely culprit for a vibration, but I do have a couple high-quality UJs lying around and could rebuild the rear shaft if I wanted to. Worth the effort?

 

I took some video of the front shaft in operation. It's at the speed where it vibrates from roughly 6:00 to 8:00 and 9:00 to 11:00. It looks balanced to me, though perhaps others will see something out of whack.


I'm a bit stumped on this now. I may try taking some video of the rear shaft to see if that reveals anything.