My recently acquired dII has a slight vibration around 40ish mph. Likely driveline. Put new front shaft in. It's balanced and has been off and on my other disco (every other oil change) its fine. It has new balanced tires, brakes are new, rotors are fine. So moving to the rear drive shaft.
Is it the same 344 ppart #? And upon visual inspection the roto coup looks fine, but should I replace anyway?
Sorry to post about part #, but couldn't find it search.

 

5th post without a response?....anyone?

 

The rotocoupling is a rubber gizmo, cracks may show up, but it has a rough life back there. Changing might save trouble later.

However, can you mechanically engage the CDL and drive without one of the shafts? That would kinda tell you for sure. You can have a front wheel drive Rover for testing.

 

done did. not the front
, but fo sho the rear..... roto should be on the parts list?

 

or that rear uj that i can not! find the part # for? or fo sho both?

 

The Microcat parts system (at lrpats.ru) shows same part number for front or rear u joint (OEM only shows on single joint on each shaft, other end is the double shaft or the rotoflex).

Here's a pix of a failed roto flex, sometimes hard to see the cracks.

 

I too have vibration that shows up right around 40 mph. I couldn't see any obvious cracks in the rotoflex joint, but please let me know what happens with yours.

 

Dusty1,
Could you please let us know how you fixed this issue? Was it finally the roto flex?
this is driving me crazy. I already changed the front shaft and I am thinking about getting it balanced (even though it is brand new).
Thank you

 

sorry, it was the forward/only u-joint on the rear shaft.
I went ahead and replaced it while awaiting roto.
even though the u-joint looked fine (caps/bearings/and all), I replaced it and tahdah.... no more vibration.
do you have the option of locking the cdl in your truck? if so, you could test drive with only 1 shaft in. that would help narrow it down

 

just because you do not see cracks in the rubber is no reason not to replace. rubber will stretch, loose its shape, become MORE flexable over time thus rendering the roto flex coupler closer to failure. Its cheap and easy to fix swap it out. if you have never swapped it out you should just do that. regardless of visable cracks.