not all rtab are the same, which one?

[radialaced]

as far as the stock rtab are concerned there seems to be two types. The plain one and the one with the flange on one side.

check out these pictures.

flange type:
http://www.rogueengineering.com/Merchant2/graphics/00000001/suspension/rtab_shims/noshim_600.jpg
or
http://images.europeancarweb.com/projectcars/0308ec_proj32506_z.jpg

plain type:
http://www.autopartswarehouse.com/sitesearch/details.php?p_id=bmw328is19961999lemforderw0133-1634486&url=L3BhcnRzZWFyY2gvQk1XX1RyYWlsaW5nX0FybV9CdXNoaW 5nLmh0bWw/YXB3Y2lkPVgxMDkzMDEwODQxVzQxMjYwNTk5YzYzNTAmYXB3a3 dkPUJNVytUcmFpbGluZytBcm0rQnVzaGluZyZnY2xpZD1DTlRN XzlfcnFZOENGUWRFRlFvZGQzYzdSdw==
or like the ones at bav:
http://www.bavauto.com/

I got m3 rtab at the dealer and they are the plain type without the flange.

does this matter?

[bmwpowere36m3]

The one w/o the flange is a "new" design, I think based on the Z4. It'll work just fine. However if you drive your car hard, these will eventually fail as well...So my recommendation is: For comfort {OE RTAB w/ a reinforcement spacer (i.e like this: http://www.ground-control-store.com/products/description.php/II=673/CA=9 )} or for performance {get a urethane RTAB (UUC, PF, etc...)}.

[Rob Levinson]

A little more clarification...

The original design of the E36 RTABs had a lip also, but different than the aftermarket bushings.

The OE bushings left room on either side, which would allow them to squish excessively, too much for sporting use. A cheap and simple fix was limiter shims that would install on either side of the bushing, such as sold by TMS.

The new OE bushings, originally a Z4 part as described in the post above, have no tab at all. The jury is still out on whether these will really provide reliable long-term service without that retaining lip or whether they might squirm out.

The more important difference to realize between the OE bushings and aftermarket urethane bushings, is that the OE bushings require some significant force to press into the arms... you have to push the bushing most of the way through.

In contrast, the 2-piece aftermarket bushings install more easily, half from each side and then a single tube put through both. You can see that the bushings themselves are split in the middle (see the line):

http://www.uucmotorwerks.com/RTAB/RTAB-250.jpg (http://www.nexternal.com/uuc/Product529)

The lip on either side of the bushing is like having the limiter shim already built in. This way, this design cannot squish out of position and results in a much more controlled rear suspension.

More details: http://www.nexternal.com/uuc/Product529

[Maj.Malfunction]

^^UUC makes a great product. I have the RTABs pictured above and they are phenominal. Not harsh at all in town and offer more than enough support for track days. I also anticipate them lasting much longer than stock.

Once again UUC with another great product.

[radialaced]

A little more clarification...

The original design of the E36 RTABs had a lip also, but different than the aftermarket bushings.

The OE bushings left room on either side, which would allow them to squish excessively, too much for sporting use. A cheap and simple fix was limiter shims that would install on either side of the bushing, such as sold by TMS.

The new OE bushings, originally a Z4 part as described in the post above, have no tab at all. The jury is still out on whether these will really provide reliable long-term service without that retaining lip or whether they might squirm out.

The more important difference to realize between the OE bushings and aftermarket urethane bushings, is that the OE bushings require some significant force to press into the arms... you have to push the bushing most of the way through.

In contrast, the 2-piece aftermarket bushings install more easily, half from each side and then a single tube put through both. You can see that the bushings themselves are split in the middle (see the line):

http://www.uucmotorwerks.com/RTAB/RTAB-250.jpg (http://www.nexternal.com/uuc/Product529)

The lip on either side of the bushing is like having the limiter shim already built in. This way, this design cannot squish out of position and results in a much more controlled rear suspension.

More details: http://www.nexternal.com/uuc/Product529

Thanks for the great clarification. I would be tempted to try the UUC, but I already have the OEM M3's, (Z4).

I know that I have to put hose clamps on them to squeeze them down to get them started. I have a few puller and press parts that I can jury-rig together to press/pull them in.

I don't have limiters though. I do however have a wonderful chunk of delrin that was cut from a rod of the stuff. It's 3" in diameter and 1 9/16" thick. I could slice four 3" round wafers from the stuff at about 5/16" thick each.

This does lead me to a question though Rob, why don't your shims have any taper to follow the curvature of the console?

Thanks

['96 E36 M3]

When I complained to my local shop about a "weird" feeling from the rear end on hard acceleration and braking they thought it might be worn RTABs. After confirming they were worn (and there was play) they suggested the TMS kit. They are installing that kit right now - with new OEM bushings - and I'm hoping for some improvement. Will report back the results.

[houstonm3]

all i know is you cant install the OE RTAB's yourself, they need to be pressed in and only a few mechanics will have that press, the aftermarket i've heard do not need to be pressed and hence are a lot easier to install.....

[Eric98Sedan]

all i know is you cant install the OE RTAB's yourself, they need to be pressed in and only a few mechanics will have that press, the aftermarket i've heard do not need to be pressed and hence are a lot easier to install.....

Anyone can do anything if they:

1. Have the means (tools)
2. Have the knowledge

[Eric98Sedan]

The OE bushings left room on either side, which would allow them to squish excessively, too much for sporting use. A cheap and simple fix was limiter shims that would install on either side of the bushing, such as sold by TMS.

In theory, but once installed the actual bushing lip(s) make zero contact with any part of the control arm, bushing bracket, or chassis, effectively making the lip(s) useless.

The bushing bracket (console) is clamped tight via the bolt, to the metal sleeve that runs through the center of the bushings. But since the busing lips don't actually touch anything, nothing prevents the console from twisting 'around' the control arm, which is the very thing the lips are sopposed to prevent.

No?

[bhallid]

all i know is you cant install the OE RTAB's yourself, they need to be pressed in and only a few mechanics will have that press, the aftermarket i've heard do not need to be pressed and hence are a lot easier to install.....

There is a write-up here (http://home.comcast.net/~matthew.c.smith/mods/rear_shock_mount/index.htm) about replacing the RTABS. It mentions that you need some type of press device. What I used (DO AT YOUR OWN RISK) - I went to autozone and rented their Ball joint press. Amazingly enough, the two plates they provide fit perfectly (one fits on the outside of the RTAB and the other side fits perfectly on the inside of the Trailing ARm. I got it all tightened down and then used an impact wrench to press it in. When you get to the last part the plate that fits on the trailing arm has to be removed and you may have to get a little creative pressing it the rest of the way in. My ball joint press (a giant C clamp) had a hollow end (hole) on the side where the trailing arm was. I was able to line up that hole with the middle of the RTAB and press it the rest of the way in. The middle of the RTAB that is metal wound up kind of sliding into the hole at the end of the ball joint press. It actually worked perfectly. It actually was easier than what it sounds here. The only thing is that I wish I had taken some pics. Go look at the ball joint press you should see everything I'm talking about.

[bhallid]

Sorry man, I posed the wrong link - here is the correct link -
http://home.comcast.net/~matthew.c.smith/mods/RTAB/index.htm (http://home.comcast.net/%7Ematthew.c.smith/mods/RTAB/index.htm)

I highly recommend buying the Reinforcement Plates.
Ground Control Street Stability Kit 60.00

http://www.ground-control-store.com/products/description.php/II=673

[Jrdeamicis]

Anyone can do anything if they:

1. Have the means (tools)
2. Have the knowledge

I did it with my unk with an air chisel and I put the two piece UUC bushings in. They are great.