polyurethane bushes

Does anyone have real word experience of using poly bushings in the front suspension. I read the enthusiastic advertising literature on poly Vs. rubber, but what are they like to live with.

Very positive from numerous RWD cars i've installed them on, never have installed them on an XI but i've heard several people here are happy with the powerflex units.

Powerflex are a good alternative to OEM, they're much easier to install and firm up the car a little bit. Make sure you grease them well with the included grease, and they'll last a while with no squeaking.

On a side note, I ran Powerflex bushings for a few years but have recently (last 20-30k miles) switched to AKG bushings. They're much firmer, and unless you use the proper grease they squeak, but they last forever. I usually only got about 40-50k miles out of a set of Powerflex control arm bushings.

Final note - use E36 M3 bushings. They're the same diameter, but centered (rather than the slight eccentric on the XI bushings), so they're much easier to install correctly. You may need an alignment afterwards, but it will still align close to factory specs.

I am running the powerflex in my front control arms and simply because of the ease of install they are awesome.

love my PowerFlex FCABS and sway bar bushings.

Im running both powerflex for both my FCARB and RTAB and love them.

Thanks to all.
My 325Xi is a smooth and comfortable Sports Sedan who's steering has started to get a little "Chevy like"
I want to regain the precision but not turn it into a go-cart.
Looks like Powerflex is the way to go.

Road test to ensue shortly, but from a mechanic standpoint they are awesome.. if they ever wear out it's a simple replacment of the inner "purple" piece, not taking the bushing off, pressing it out, etc. worth it in my opinion... oh yea... much more solid and less suspension stiction

side note... not to start a wild divergence...I use Silver Anti-Sieze by permatex on all my poly bushings with great results. When I opened the tube of "lube" sent by powerflex it looked like "copperslip"..... copper based anti-sieze.. I saved those packets for another day

I Look forward to hearing how the road test went.
Were the supplied bushings of the asymmetrical type, that is what seems to be shown for the Xi.
The factory bushings seem symmetrical, so the change will affect the suspension geometry.

Factory xi bushings are also asymmetrical (I know I've replaced several sets). its hard to tell if the bushing is really worn out. It is also explained in the Bentley manual. I believe the hole offset should be placed towards the center of the car per OE spec.

I have news for you guys- the stock bushings are worn after 5k miles. Buy the centered powerflex for e36 m3. Use the grease that comes with them. Measure. Then never worry about FCABS again.

Only stuff I found to work better than anti sieze is this:

http://www.amazon.com/Energy-Suspens...pension+grease

It's a teflon based lubricant, so it's sticky, slippery, and stays put. I found anti sieze to dry out after a few months and start to prevent movement (especially in cold salty conditions!).

Originally Posted by athayer187

Only stuff I found to work better than anti sieze is this:

http://www.amazon.com/Energy-Suspens...pension+grease

It's a teflon based lubricant, so it's sticky, slippery, and stays put. I found anti sieze to dry out after a few months and start to prevent movement (especially in cold salty conditions!).

I've heard great things about that stuff, I should get some to keep around the shop. What I also heard is don't let it touch anything you don't want lubrication on (including you!) it works "too good".

Can someone post the PN for suggested E36 M3 FCABs please? Also would you suggest replacing any other front suspension components at the sometime? I will likely use an Indy shop and do an alignment at the same time. My XI has 105k and the steering wheel shakes abut around 55 mph. After reading a bit it sounds like its FCABs gone bad.

Originally Posted by shadow330xi

im running both powerflex for both my fcarb and rtab and love them.

+1

I don't have any direct knowledge for use of the centered e36 m powerflex bushings on the xi. Many people swear by them for the XI. I think they were likely the best option before Powerflex apparently redesigned the xi bushing and corrected some of their earlier issues with this bushing.

Maybe there are other differences but from what I can tell (I'm sure I will be corrected in a very polite manner) The e36 m and the xi versions appear to be very similar in design and material, A firm rubber outer bushing with a Poly blue/purple inner bushing. I don't know if there are differences in durometers in the materials. Maybe someone who has used both can chime in here but i suspect they are the same. The main difference touted is that the e36 m version is centered where as the xi is offset slightly as per the OE FCAB. To some this is an important difference, maybe especially if you track your car and/or have otherwise altered the geometry. There is much debate on this point. For me I choose to trust the BMW engineers and I use the xi version which keeps the OE geometry with my stock OE ride height. My car is a daily driver and it aligned beautifully and handles really nice I'm very pleased.

The other difference is that the new XI bushing design fills the entire gap between the lollypop carrier and the shoulder on the end of the arm, where as the E36 M version leave a gap of about 10 mm when installed. For some this is not a problem, but some have resorted to filling the gap with a hose clamp to keep the bushing in place.

I may be missing some other important distinctions and maybe others can fill in the gaps. I just raise these points of distinction between the e36 M and the XI specific bushing so that you and others can make an informed decision and decide if this is a proper modification to your car. Despite the differences in the two designs I think most everyone who has use the powerflex bushing has reported favorably, though I am sure some will disagree

TC Kline is building a coilover setup for my 2003 XI and TC was pretty adamant that rubber bushings should be used. I've used poly on my Rovers and never felt a difference.

If you stick with rubber bushings, get OEM they will last a lot longer then the cheap stuff.

Unless there is something proven better than OEM that's all I use.