The bushings I purchased were Genuine Meyle HD. They are hollow with only two rubber attachment points inside the body of the bushing. The units I removed were Lemforder parts and looked exactly the same (not fluid filled) and I have had this X5 since it had 55,000 miles. I highly doubt the stock bushings were replaced before this. The BMW part catalog shows the same pat number for all e53 X5 models- 33316770454. This pic is exactly what you receive when you order Meyle HD Bushings:



Green Dragon: Regarding the shrinkage of the urethane in the stock bushings, meaning if it separated from the inner casting of the bushing it did not. They have different durometer blends available. I just went with 80a because of the possible transmission of noise to the cabin. At 80a it does not transmit any noise. Regarding filling the other bushings it may prove problematic because the pieces would be as you had mentioned. Milled pieces that are pressed in then the inner sleeve run through. For the rear control arms a better solution would be spherical bushings similar to these:

http://mooseheadengineering.com/#!/~...126&id=6647004

I have these on my e34 touring and they work great(front upper control arm) the lowers would needs to be the arms out of the e31 8 series to match($350.00 for the set). I have read on some of the e39M5 boards that a guy came up with the same type of setup but he was charging $600.00 for a set. The e39 arm is very similar to the one in the X5.

Sphericals would be the way to go regarding longevity. Much more solid units and rebuildable.