Little history. The truck sat for sometime, have been working to get it back on the road. After doing quite a few other things, it is getting there. Had a Tom woods on that gave up,, but didnt totally break. Installed a lucky 8 driveshaft a while ago, but wasn't really able to drive it until recently. Got new tires on it today and still have a vibration around 30 mph. Did I not get the driveshaft aligned properly? I read about needing to rotate it possibly. Do I just need an alignment? Haven't driven it much, or faster than that. Steering wheel doesn't really seem to shake, but feels like the whole truck gyrates.

Thanks for any advice!

 

The rotoflex coupler is probably shot.

 

that is usually a visible thing (rubber torn or mangled) correct?

 

Generally, but not an absolute.

Check for play in everything, and make sure everything is lubed. A vibe at 30MPH, my money would be on a driveshaft.

 

Check for play in the output bearings on your t-case.

Why did your TW fail?

 

My son had been driving it, I can only assume he didn't lube it.

 

That'll do it.

How much lift are you running?

 

None. Seems like the rotoflex coupler might be a possibility and probably needs to be done anyway.

 

Let me know, we have a kit for that:
Lucky8 D1/D2 rear drive shaft conversion kit ? Lucky 8 Parts and Accesories for Land Rovers

 

Coupler replaced, vibration remains. It's only on acceleration and actually starts at about 25mph.
Stumped.