AKG Poly RTABs or OEM rubber RTABs?

[coolguy147]

Can't decide. Pros and cons?

[ZoO]

I read that poly bushings are stiff and squeak. I bought oem, waiting on winter break to install.

[dmalhi1]

i went with the ireland engineering rtab's. no squeaks, no noises, excellent product.

[Mr Bingley]

Potential to squeak with poly and nothing wrong with OEM design argues in favor of OEM on RTAB's.

[BimmerBreaker]

My train of thought was unless I had a reason to go poly, I went OEM. All my bushings - front and rear - are now new and OEM, except the IE green subframe bushings which are the one bushing I think is best as poly (I'm not sure exactly why but Randy said so and thats good enough for me!)

[Vintage42]

... IE green subframe bushings which are the one bushing I think is best as poly (I'm not sure exactly why but Randy said so and thats good enough for me!)

http://www.bimmerforums.com/forum/sh...-Mount-Failure

[328 Power 04]

I have IE trailing arm bushings on the roadster, bathed in grease, and after a short time they squeak.

I have AKG trailing arm bushings on the coupe, bathed in grease, and after a short time they squeak, and pop.

[JoshS]

It's simple: there's nothing wrong with the OEM rubber RTABs. The reason why aftermarket makes sense in many of the other applications on these cars is because the stock bushings have voids, which makes for a better ride but is a lot less precise. That's not the case with the RTABs, which have no voids.

And rubber is much better for rotating applications than poly, for which you have to maintain lubrication to avoid noise.

[lokijibber]

I went with poly because I wanted to really limit the movement. I don't notice a squeak, but that doesn't mean they don't exist. The car is so loud that I probably just don't hear it.

Changing them is a bitch. It really makes sense to do the RSFBs at the same time since you're essentially doing the same RnR for both.

[saneesh8]

I went with Powerflex for RSFB and Lemforder (OEM) for RTAB. So far no issues. Replaced it like 9 months ago and still no issues and no noise.

[s8ilver]

I drive about 900 miles in 9 months, so maybe not relevant to all

What sort of mileage on your new bushings? I just ordered OEM LCAB and RTAB and am sorting RSFB this week (IE or Powerflex, possibly AKG). I don't even get my car for a month, but I decided a full suspension/bushing overhaul is in order ('99 Z3M with 52k miles...well, 53k miles after I drive it home from L.A. to Denver!!!). I've also decided to replace springs and dampers (went with H&R/Bilstein Sport package on special from Turner yesterday). I ordered new F&R bump stops and spring pads as well, but not sure what else could need R&R. Oh, also some new aluminum/poly RSMs.

What else should I replace when in there?

[coolguy147]

I drive about 900 miles in 9 months, so maybe not relevant to all

What sort of mileage on your new bushings? I just ordered OEM LCAB and RTAB and am sorting RSFB this week (IE or Powerflex, possibly AKG). I don't even get my car for a month, but I decided a full suspension/bushing overhaul is in order ('99 Z3M with 52k miles...well, 53k miles after I drive it home from L.A. to Denver!!!). I've also decided to replace springs and dampers (went with H&R/Bilstein Sport package on special from Turner yesterday). I ordered new F&R bump stops and spring pads as well, but not sure what else could need R&R. Oh, also some new aluminum/poly RSMs.

What else should I replace when in there?

Honestly, I wouldn't even bother replacing anything if that's all you drive.

And, 53k is nothing compared to 185k lol :P

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[s8ilver]

Honestly, I wouldn't even bother replacing anything if that's all you drive.

900 miles at my home track would warrant some replacement bushings I'm sure. It's a brutal course!

http://highplainsraceway.com/track-i...-and-location/

However, I don't think my new M will be a track car. I think I'll preserve it and just use it as a good weather cruiser. I'm a bit OCD with the OEM rubber parts though. IMO, regardless of mileage, rubber is on its way out after 15 years. Of course, probably depends on storage and climate as well; just too many variables. Since I'm doing suspension, I figured a few more bucks while everything was apart was a no brainer.

[coolguy147]

900 miles at my home track would warrant some replacement bushings I'm sure. It's a brutal course!

http://highplainsraceway.com/track-i...-and-location/

However, I don't think my new M will be a track car. I think I'll preserve it and just use it as a good weather cruiser. I'm a bit OCD with the OEM rubber parts though. IMO, regardless of mileage, rubber is on its way out after 15 years. Of course, probably depends on storage and climate as well; just too many variables. Since I'm doing suspension, I figured a few more bucks while everything was apart was a no brainer.

I would put Poly in the rear subframe bushings though!

I know the downside to rubber is that it basically needs to be pressed out... and pressed back in.