Have some one done this (balancing the drive shaft)? how much did it cost you? did it solve the issue?
I have been reading all the threads relating to vibration and started getting frustrated with the results. It seems like luck have to be involved to get this issue resolved.
The problem: Vibration at 40's and 70's MPH
Tried: Replaced Front Shaft, changed u-joint and rubber rotoflex from rear shaft, balanced all tires.

help!!!

 

I had mine balanced and it didn't help, though my shop's balancer looked approximately 100 years old. I bought a different used shaft and it got a bit better. I just think these things are vibration prone.

I also wonder if the 40mph vibration is the shaft, and the 70mph vibration is a dying bearing in the front diff. For me, the 70 mph vibration is intermittent and almost more of a noise than an actual vibration, so I really don't know what to think about it.

 

When I first bought my Discovery I thought the drive shaft was going to fall off.

I greased it and the vibration went away.

 

My Disco would vibrate between 70 and 80 mph. I noticed a large weight on the front DS was worn away on the leading edge most likely from grinding on a rock. There wasnt much missing so I tried a hose clamp with the screw portion aligned with the missing weight material. Vibration is now gone.

 

Propshafts need to be balanced. New ones are balanced at time of manufacture. Old ones need to be balanced if a weight is lost. When you rebuild one it often needs to be balanced.

 

I must be showing my age, I rarely go above 70!

 

"Propshafts need to be balanced. New ones are balanced at time of manufacture. Old ones need to be balanced if a weight is lost. When you rebuild one it often needs to be balanced."

My 2004 D2 had original front propshaft with no grease circs, but was otherwise not worn or having any particular problem; it ran smooth as butter, with no vibration at all. So, I simply had to work on it, to install u joints with grease circs, and chose the ones with the circs at the ends of each u. joint, rather than the ones having the circs at the inner cross. I greased them all well, installed them, and now I have a low rumble vibration---by feel; not by sound--at around 40-50 mph and faster, but only when accelerating; none at all with foot off accelerator at any speed. I had a notion that those damn grease circs at outer ends of u. joints would make whole thing more off balance, but ignored those thoughts. Now, I am thinking that this vibration, over long term, could lead to quicker failure of bearing at outer end of front transfer box housing. Maybe I should take it to a garage that specializes in balancing these shafts, what you think? Or, maybe I should just tear it apart myself, and install new u. joints same as original type, ones with circs in inner cross, since it would be same as original, and have less weight around outer perimeter of u. joings, from circs at outer end of u. joints, what you think?

 

back to the basics:
Have some one done this (balancing the drive shaft)? how much did it cost?

 

When you consider the small size of the balancing weights attached 'spot welded' onto a propshaft it puts it into perspective that the additional weight of grease nipples on a UJ will imbalance the shaft. If this appears to be the case then apply the grease and remove the grease nipple and screw in a cap head grub screw flush to the UJ spider which I believe is a 6mm thread (needs checking) If you replace the two cardan UJ's ensure you have the grease nipples on opposing sides. If refurbishing propshaft's always ensure you mark the flanges and UJ's relative to where they are/were before dissembling otherwise the result can be an imbalanced shaft as they are balanced as a complete assembly. As for the cost of re-balancing, some years ago in the UK I paid GBP£25 for two shaft's on an old series 2A Landrover which at todays prices would probably equate to GBP£50-60 or USD$75-90, therefore I would budget for a price of USD$50 each shaft.

There is also the case where a failing differential pinion bearing may cause vibration which would be disguised and magnified by the propshaft. Worth a check on the pinion bearings once the propshaft is removed.

 

My French friends: "When you consider the small size of the balancing weights attached 'spot welded' onto a propshaft it puts it into perspective that the additional weight of grease nipples on a UJ will imbalance the shaft." THAT IS WHAT I THOUGHT, AND NOW AM SORRY I DID'T LISTEN TO MY THOUGHTS, WHEN I WAS WORKING ON IT. " If this appears to be the case then apply the grease and remove the grease nipple and screw in a cap head grub screw flush to the UJ spider which I believe is a 6mm thread (needs checking) If you replace the two cardan UJ's ensure you have the grease nipples on opposing sides." I THOUGHT OF THAT TOO, BUT WAS SO MUCH IN A HURRY TO GET IT DONE, THAT I THINK I IGNORED MY THOUGHT ON THIS TOO, AND PUT THEM ON NOT OPPOSITE, SO I WILL NOW CHECK, AND MAY HAVE TO RE-DO MY WORK. DID I REMEMBER TO SAY THAT I HATE THIS U JOINT, PROP SHAFT WORK, ESPECIALLY ON THIS CARDAN TYPE? I HAVE WORKED ON A LOT OF U JOINTS IN THE PAST, BUT NOT ON A SINGLE CARDAN TYPE, NOR ON ONE AS PAINFUL AS THIS ROVER TYPE--TOO OLD; DON'T HAVE THE PATIENCE FOR IT ANY MORE, BUT WILL HAVE TO WORK THROUGH IT. Thanks to my French friends.