Urethane filled subframe bushings
 

The X5's rear subframe bushings were doing the usual creaks and squeaks calling for replacement. Having purchased the Baumtools bushing tool I decided to not buy the Powerflex bushings and went with the stock bushings but with a twist. I filled the four of them with 80 Durometer polyurethane. I did this back in the day on my e21 and my e28.

Here is an example of how they are filled (minus all of the bubbles):

http://img241.imageshack.us/img241/9413/bush18oi.jpg


The two part urethane kit is from McMaster-Carr McMaster-Carr

Cut the casting flash webbing from the middle of the bushings, cleaned them out with acetone and set them to dry. You can cover the bottom part of the bushing with clear packaging tape so the poly does not run out. Some have also used quick set plaster for this. Once the bushings are sealed mix the two part urethane per instructions and after two minutes pour the mix into the molds. Once kit is enough for two bushings. The urethane flows very well and does not cause the bubbling shown in the pic above. After three to four days they have cured enough that you can install them into the X5.

Comparisons: Compared to the shot bushings it is night and day. Compared to the Powerflex bushings in my 5 series touring the filled bushings make less noise but are just as firm. Ideally the filled bushings should last a little longer than the stock ones with the empty voids. No additional noise (diff whine, suspension creaks , ect ) is transmitted into the cabin with these filled bushings.

Cost comparisons between bushings:

Powerflex - $487.99 Pelican

Stock - $38.97 ea x 4 = $155.88-BMA
Urethane kit- ~$32.00 ea= 64.00
Total $219.00

The leftover $268.99 was put into the Baumtools Tool that made short work of extracting and installing the bushings.

All in all I felt it was a worthwhile mod. YMMV.

thumbs up
awsome way to save a good amount of cash
can u post pics of the bushing tool?

Same as the rental tool here on this board:

http://www.xoutpost.com/bmw-sav-foru...ol-rental.html

Dude, that's brilliant! :thumbup:Now I'm thinking of all the bushings I can make/modify. Are the rear sub-frame bushings the only ones that are that cost effective to this approach in comparison to the power flex? Did it shrink much?

I was helping a buddy out with is e46. He needed to replace the rear control arm bushing, so I had him pick up a urethane set for longevity and performance(and price was good)Put them on, but there seems to be some play b/t the housing and bushing. Damn it! I may try this to to help firm it up, maybe a slightly firmer blend with less shrink?

Thanks Man! Good Job!

Great and awesome job with the ingenuity enough to offer a much more affordable to Powerflex urethane, if one wants to go that route.


However, one can also buy Meyle HD subframe bushings (which are solid rubber and not fluid filled like stock, they also sell HD thrust arm bushings for the front) for about 160 for the set of 4, which is basically equivalent to the price of a stock bushing.


Just another alternative for anyone who is replacing theirs and would like to know their option. I for one would not spend the money on Powerflex, and probably would not have the need to spend the 60 extra bucks on urethane liquid kits, so the Meyle HD would give me all I need, upgrade from the fluid-filled factory part, and longevity and quality.

Perhaps you should get a patent for that idea and go on SHARK TANK. :thumbup: :thumbup: :thumbup:

Interesting.....Although I've seen this done before from the import scene would have Never thought to apply it to the E53 bushings! Sounds like they're a good "all around" sort of solution. Nice job.

Nice effort. My subframe bushings are due soon, but with 140k miles, I don't have any problems with putting the OEM (Febi, Lemforder).

The powerflex are so ludacriously overpriced, I have no desire for them regardless of performance.

Thanks for sharing.

Go with Meyle HD on your souped up X if you do replace, they are pretty much same price as OE bushings!

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:

http://8.19.68.55/images/catalog/full/33316770454MY.jpg

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.

I have spherical rod end suspension pieces on both of my Lotus and if you are using the car as a DD you don't want them.

Outstanding!
I too have issued MEYLE HD replacement parts.
Good stuff at a reasonable price.
At ~175k I have a few out these to do.

as stated I have these in my daily e34 (front UCABs) and I have no issues at all. I doubt putting these in the rear will cause any issues.

Hey OP, do you have the tool available for rent? I'd like to get myself a set of 4 and pour urethane into them as well a la your method, just don't have a line on a local tool rental.

Was wondering if I could put a flat piece of modeling clay under the bushing and place the bushing into the clay, to stay in place and also to keep the urethane from spilling out, once cured, I should be able to peel the clay away from the bottom of the cured bushing right? Should be a little bit of a more "precise mold" on the bottom as opposed to using packaging tape right?

Let me know your thoughts and if you have the tool, I'll gladly pay for the rental and insure it on the way back to you.