PowerFlex Rear Trailing Arm Bushing RTAB DIY

Here's a simple DIY for replacing your RTAB's.

1) Jack the rear of the car up and support it on jack stands
2) Follow the wire(s) on the trailing arm to locate the little black box in front of the trailing as pictured.


3) Unclip the wire(s) from the body first, then open up the box and remove the blue and or black connector. Separate the connector by pressing the release tab and pull in apart.

4) To save yourself a possible need for an alignment, scrib an outline around the trailing arm carrier. Then take your jack and support the trailing arm. Remove the three 18mm bolts that attached the RTAB carrier to the car.

5) Once the bolts are removed, lower the jack. You may need to wedge a block of wood as pictured to get the trailing arm low enough to remove the bushing

6) Take a breaker bar with an 18mm socket and an 18mm socket or wrench to remove the bolt that passes through the carrier.

7) Now to get the bushing out. The simple super fast way.........get yourself a tool like the one I have pictured.
http://www.mistools.net/shop/article...1%26aid%3D1%26
With the proper tool, the bushing will be out in a minute!

8) Next, get yourself copper based anti-seize. This is a must if you don't want squeaks, creaks or clunks

9) Take a wire brush or some emery cloth and clean out the inside and outer edge of the trailing arm.


10) Once cleaned, generously apply the antiseize to the entire trailing arm as pictured

11) Take your PowerFlex RTAB's and generously apply the antiseize as pictured, including the inside where the bolt will pass through


12) Take the RTAB's and install them in the trailing arm. Apply antiseize to the barrel and push the barrel through both bushings. You may need to tap it with a hammer to get the barrel through

13) Take the carrier and apply anti seize as pictured

14) Take the carrier bolt and install it

15) All that is left is to lift the carrier into position and install the three bolts. Use a jack to support the trailing arm while guiding it into location. If you are strong, you can just get on your back as I did and push the trailing arm up with one arm and use your ratchet in the other hand to install the three bolts.
16) Road test to follow once I get my ECU back from ESS.......

Great job on the write-up! I need to do mine soon and this will come in handy

One question though. Any chance you'd have the measurents of that tool
So I can make my own prior to the install?

very nice write up...and even better then the write up is the link you provided for the tool....that is the cheapest i have every seen it for....BMW wanted $300 plus for that same tool...yeah its not oem but it gets the job done...thanks for posting!!


Im saving this thread!!

You're welcome guys........

Unfortunately I just sold and shipped the tool to another forum member named "syazoo". You could PM him for the measurements or just buy it from him when he is done with it. It may be tough to measure as the piece that slides through the trailing arm with the bushing is beveled on both edges.If you were to buy your RTABs in advance and measure the circumference, you'd then know what size/bevel you would need.

The tool makes this DIY very simple 2 hour project. Without it, it would be a struggle cutting those bushings out as others have done.

As a side note, if you plan to use this DIY as reference for replacing your RTAB's with OEM ones, make note of the angle\position of the RTAB carrier before you remove the bolt that passes through it. Otherwise you will preload the bushing which is a no-no.

Originally Posted by fmzip

You're welcome guys........

Unfortunately I just sold and shipped the tool to another forum member named "syazoo". You could PM him for the measurements or just buy it from him when he is done with it. It may be tough to measure as the piece that slides through the trailing arm with the bushing is beveled on both edges.If you were to buy your RTABs in advance and measure the circumference, you'd then know what size/bevel you would need.

The tool makes this DIY very simple 2 hour project. Without it, it would be a struggle cutting those bushings out as others have done.

As a side note, if you plan to use this DIY as reference for replacing your RTAB's with OEM ones, make note of the angle\position of the RTAB carrier before you remove the bolt that passes through it. Otherwise you will preload the bushing which is a no-no.

I can't believe I never thought of measuring the bushing itself

Thanks for the heads up

Thank you!

^^^^much obliged~

Good write-up!
But I've heard that one' should (put the car on tires) aka; preload all bushings on bimmers before fully tightening them down...!?
Ore is that just for OEM bushings?

really nice write up.

Originally Posted by Tele

Good write-up!
But I've heard that one' should (put the car on tires) aka; preload all bushings on bimmers before fully tightening them down...!?
Ore is that just for OEM bushings?

That is for OEM bushings...you don't have to be concerned about preloading these as the design is different

Originally Posted by Sharky06

really nice write up.

Thanks!

Originally Posted by Tele

Good write-up!
But I've heard that one' should (put the car on tires) aka; preload all bushings on bimmers before fully tightening them down...!?
Ore is that just for OEM bushings?

I can guarantee you that you won't be tightening up the bolt that goes through the RTAB and the console while the car is resting on the suspension.

The rubber OEM bushings still need to be preloaded but that is accomplished by adjusting the angle of the console relative to the trailing arm and bushing prior to raising the console back up into the chassis and bolting it into place.

Poly bushings don't need to be preloaded because they are loose enough to spin within the arm.

Originally Posted by TxZHP04

I can guarantee you that you won't be tightening up the bolt that goes through the RTAB and the console while the car is resting on the suspension.

Very good point my friend

I have 67k miles and just installed Powerflex FCAB's a little while ago and love them....should I do the RTAB's now or can I wait a little? Any risk running the OEM's in the back with the upgrade in front?

I didn't feel mine were shot at 70K but after I replaced them, it totally transformed the car.

Did you notice any difference in feel with the FCAB's? I don't want to feel more of the road than I do right now which is why I haven't upgraded. Got my factory ones replaced for free right with new lower control arms right before I turned 50k.

I wouldn't say there is any risk with leaving the back OEM while running Powerflex in the front. I would guarantee if you like the front ones, you will LOVE the addition of the rears. My car drives like it is on rails better than ever!

Yeah, there was a big difference however the big difference was between the shot OEM's and the new Powerflex. If I had new OEM's to compare side by side with the new Powerflex I don't think the difference would be that pronounced. I like a stiff ride but what attracted me to the Pflex is the longer lifespan than the OEM. Really don't want to have to do it again.

I'm feeling inspired to do the RTAB's now....

^^^^Just do it