I,m getting what I feel determined as a bad driveshaft vibration, but I'm getting a bit stumped. I believe I had narrowed it down to a bad front driveshaft by removing the shafts individually.
A short history. New tires and a few days into it I noticed a vibration. Rebuilt the rear shaft and afterwards noticed that it seemed a weight had rusted off. Ordered a new shaft (figured I would have the old one re-balanced and save as spare). Also ordered a new front shaft. Installed both and vibration was still there and seemed to get worse. I was concerned with the new front one as it was a cheaper Ebay and it had too many weights on it for my liking.
OK, so having both new shafts still installed I removed the rear and test drove. Was way worse as far as acceleration vibration. I then re-installed the rear and removed the front. No vibration. I then re-installed my OLD front shaft that I then noticed a weight was missing on that. Thought maybe this was my issue to begin with. Yes, I taped a couple of washers on this shaft where I saw the weights were missing. Installed it, test drove and little to no vibration at all. Concluded I got a crap front shaft from eBay. Ordered a new one from Lucky 8, .. the $208 one. Yesterday with still my old front shaft on I really started feeling that vibration under power again, the one we all feel is a bad shaft. It was getting pretty bad. In the afternoon I threw on the new Lucky 8 shaft and test drove. Felt as bad, or maybe a touch worse. So, WTF? Is it possible I got another bad shaft, or do I have issues I don't understand?
Thoughts? Discussion?
Thanks

PS. So the vibration happens under acceleration starting around 45 to 50. Throw it in neutral and its as smooth as silk.

 

So you had no vibration until installed new tire's,?
But then again no vibration without front shaft,?
Both new shafts can't be bad, (even though possible),,,
I would guess a bad front output flange on transfer case perhaps, take front shaft off & check T-case flange for excessive looseness (side to side), could be a bad bearing causing vibration under pressure,

 

This D2 is new to me. Only a few months. The tires on it were pretty chopped so I dont think I could feel the drivetrain vibration. I'm pretty sensitive to driveline vibration. New tires on and I felt it. Felt like it grew worse. I didn't like the new tires so got new BFGs. So, not that it was suggested, but tires are not the issue, though I think I have a bad wheel, maybe two.
Anyway, I did all I could to see if any of the yokes had play, side to side, in and out and they all 'seem' rock solid.

 

Did you fully grease/lube the U joints before you installed the new shafts? And yes I know they come "pre-greased" but that doesn't matter. Some will not take a full grease even on the bench.
It's B$ and lazy, but you would be amazed at how tight they slam those bearing caps in. And they look like the U joints are moving until under load, then not so much.
Also check if the zerks are phased proper, like

 

Thanks. Yes, I greased after install. My grease fittings are on the endcaps on all three U-joints.

 

Didn't you put in a new lift recently? What type and how high?

Remember you checking toe, maybe you should check it again...if vehicle has settled or changed. Can't remember if you were doing this before or after the lift?

Brian.

 

Hey Brian,
Yes, I put in new +2 TF springs and shocks, but did not change the lift as to what was in there. (By the way, I haven't forgotten about you). This vibration is for certain a drivetrain vibration and not an alignment issue. I found a driveshaft shop about an hour away that I believe can re-balance one of my now three driveshafts. Think it's worth it to start there to get "balancing" off the table as the issue or not.

 

You can also buy a spacer from AB for 30.00 that is supposed to help with lifted LR's.

 

What wheels do you have? I had a vibration at 45 mph it had rannge rover wheels installed, which needs concentric rings one of mine was missing, installed the right rings which centered the wheels and the vibration was gone

 

Drove a but today. I can start to feel this driveline vibration at 30 mph. Only when under acceleration. To me it really feels like a bad U joint, but I find this unlikely as all are new on all the shafts. When I let off the gas the vibration goes away, yet I'm not getting that typical vibration when you let off the gas hard that you get with a bad U joint. I would think that if it was an un-balanced shaft that the vibration would remain when coasting. When I coast, all is smooth a silk.
Driveshaft shop was closed today.

By the way, my wheels are not hubcentric. In reading I hear many don't see it necessary on vehicles like these. That can be another topic.