sealed spherical RTAB.... from a camry?!? [Archive] - BMW E46 330 ZHP For Sale Forum

slater

05-23-2018, 10:11 AM

Me too! I love it when people make the effort to find solutions like this.

I'm interested in the longevity though; Spherical bearings don't do well on the street in my experience, at least not in the Northeast because of all the G-damn potholes.

Only $17.64 at Amazon right now... If they're stiffer than OEM, seems like it'd be a great idea! (Though I wouldn't tell too many people I put a Camry part on my ZHP.) :o

LOL!

as for the longevity... the OEM upper-outer rear control arm bushings are these same design, so you're already running sealed spherical bearings on your car. :) on the M3, both upper-outer and lower-outer rear control arm bushings are this design. it's a nice upgrade for us non-M guys to put the upper bearing in the lower position (i've done this); it helps promote proper wheel alignment.

spherical bearings do fine on the street, if used in the right locations. in regards to the RTAB location, in my opinion this bushing should not be absorbing impacts (that's the job of the spring and shock); it also needs to articulate on multiple axis, which the rubber bushing does, but it's sloppy and it wears out quickly. poly prohibits the multi-axis movement, and can bind. spherical allows full articulation, with precision. i love mine.

I have only seen the stock rtab that the zhp that is made of rubber has and haven’t looked at the spherical rtabs. So these are full of metal?

yep; the rubber is purely to keep the grease in and the contaminants out. :)

san

05-23-2018, 10:13 AM

LOL!

as for the longevity... the OEM upper-outer rear control arm bushings are these same design, so you're already running sealed spherical bearings on your car. :) on the M3, both upper-outer and lower-outer rear control arm bushings are this design. it's a nice upgrade for us non-M guys to put the upper bearing in the lower position (i've done this); it helps promote proper wheel alignment.

spherical bearings do fine on the street, if used in the right locations. in regards to the RTAB location, in my opinion this bushing should not be absorbing impacts (that's the job of the spring and shock); it also needs to articulate on multiple axis, which the rubber bushing does, but it's sloppy and it wears out quickly. poly prohibits the multi-axis movement, and can bind. spherical allows full articulation, with precision. i love mine.

yep; the rubber is purely to keep the grease in and the contaminants out. :)

Ah gotcha, thanks!

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Sockethead

05-24-2018, 06:57 AM

Next time you have your car up in the air, use a prybar to flex the rear trailing arm, you won't believe how much movement the rubber bushing allows!

slater

05-24-2018, 08:22 AM

Sockethead

05-24-2018, 08:28 AM

That's built in rear steering :)

cornercarver

05-24-2018, 12:49 PM

in regards to the RTAB location, in my opinion this bushing should not be absorbing impacts (that's the job of the spring and shock);
All of the suspension components take some amount of impact. The force a pothole exerts on the tire/wheel actually has a substantial horizontal vector... The reason the wheel only moves vertically is because it is restricted laterally/ longitudinally by the control arms.

There are definitely impact forces acting on the joints. Some joints see more impact forces than others though, and I think because of the rear trailing arm's orientation, the RTAB sees more impact forces than those control arms which are closer to perpendicular to the car's axis.

Anyone think a stiffer RTAB would affect stresses imparted to the RACP? I know there have been arguments against poly bushings in the rear because they are believed to accelerate RACP failure, but considering the RTAB is isolated from the subframe assembly, is it logical that a stiffer bushing here actually reduces RACP stress?

slater

05-24-2018, 05:01 PM

There are definitely impact forces acting on the joints. Some joints see more impact forces than others though, and I think because of the rear trailing arm's orientation, the RTAB sees more impact forces than those control arms which are closer to perpendicular to the car's axis.

it also sees a lot of twisting force when power is trying to be applied to the ground.

but as far as impact absortion goes, i find the car rides smoother and absorbs bumps better with the spherical RTABs.

Anyone think a stiffer RTAB would affect stresses imparted to the RACP? I know there have been arguments against poly bushings in the rear because they are believed to accelerate RACP failure, but considering the RTAB is isolated from the subframe assembly, is it logical that a stiffer bushing here actually reduces RACP stress?

this is a great discussion topic.

from my unprofessional engineer's mind, the more i think about it, the worse poly is as a choice for the RTAB location. ultimately, they restrict trailing arm articulation as they will bind under the angles asked of them - how this translates into RACP stress, i can't seem to visualize - but, i can see how it might cause RTAB pocket stress. and as such, rubber bushings with aftermarket 'limiters' should do exactly the same thing.

in this respect, the spherical should actually be the best choice as it will restrict movement even less than the OE rubber bushings.

i can't recall if vince (creator of the VinceBar) has mentioned this or not. i'll have to ask him. i'm pretty sure he runs the BW sealed spherical RTABs on his supercharged M3.

danewilson77

05-24-2018, 05:19 PM

Putting Camry parts on a ZHP?

BP's head exploding in... 3.....2.......1.......boom

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slater

05-24-2018, 06:25 PM

Putting Camry parts on a ZHP?

BP's head exploding in... 3.....2.......1.......boom

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LOL!

az3579

05-25-2018, 03:48 AM

Putting Camry parts on a ZHP?

BP's head exploding in... 3.....2.......1.......boom

Sent from my SM-G955U using TapatalkI actually don't care about this lol

Interesting idea.

Now if it was a Prius part, I would have the urge to burn down whatever it was installed in as it would forever be tainted.

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cornercarver

05-25-2018, 05:06 AM

How about a Camry hybrid? :biggrin

slater

05-25-2018, 05:21 AM

i can't recall if vince (creator of the VinceBar) has mentioned this or not. i'll have to ask him. i'm pretty sure he runs the BW sealed spherical RTABs on his supercharged M3.

i confirmed that he does indeed have these.

which does not mean anything, however he is an ME and has done probably the most thorough independent testing and research on RACP failure, so.... take that for what it's worth. :)

How about a Camry hybrid? :biggrin

LOL! (poke, poke!)

i think tesla runs these too. :rofl

az3579

05-25-2018, 11:02 AM

How about a Camry hybrid? :biggrinDon't care if it's not a Prius. [emoji4]

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Hermes

06-03-2018, 08:24 AM

While the bushings themselves might be good, I don't like Moog. Is there a better version available?

ZHPizza

08-13-2018, 07:51 AM

Finally got around to ordering these guys as I collect parts for a winter suspension refresh. Wish I could find something similar for the FCABs!

bimmerteknik

08-19-2018, 02:35 PM

ZHPizza

08-19-2018, 03:58 PM

Just wanted to share, I found a 14mm OD and 12mm ID slug at 2” in length via a company in Asheville NC. This should allow use of stock hardware and rtab bracket without drilling it out.

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F12 3048344479

Sent from my iPhone using TapatalkPerfect. I went ahead and drilled my brackets out to 9/16" as it wasn't much of a jump at all. Haven't installed yet, but have test fit one of the bearings. Had to bend the bracket out a touch to fit the new bearing as it's slightly wider than OE.

https://uploads.tapatalk-cdn.com/20180819/81c62c73bc6c63587910de21884cfa5f.jpghttps://uploads.tapatalk-cdn.com/20180819/6691c9dab8b676227c58b44a48657cec.jpghttps://uploads.tapatalk-cdn.com/20180819/e9008d11cd8773731cc3916137c4ce46.jpghttps://uploads.tapatalk-cdn.com/20180819/baac71fea94557af169a410d83c60177.jpghttps://uploads.tapatalk-cdn.com/20180819/9e6460eef5e2fb9f929a2fb20c29cea1.jpghttps://uploads.tapatalk-cdn.com/20180819/26ed91ffd3db733a1a7e39ad7e36c53d.jpg

bimmerteknik

08-19-2018, 07:14 PM

I like your adjustment method[emoji106]

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YoitsTmac

08-20-2018, 12:49 AM

I don't understand, what's going on with all the washers here? Since I picked up a new E46, I might try this since it's all stock back there.

ZHPizza

08-20-2018, 04:37 AM

I like your adjustment method[emoji106]

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https://vignette.wikia.nocookie.net/meme/images/9/92/Improvise.jpg/revision/latest/scale-to-width-down/310?cb=20171031055222

I don't understand, what's going on with all the washers here? Since I picked up a new E46, I might try this since it's all stock back there.

See in the first pic how my new M14x75mm bolt is not fully threaded? I needed to cover that area so that I could turn the nut on the threads without it bottoming out. Happened to have a bunch of M14 washers in the box, so I used those. Could have used a large socket, piece of pipe, etc too.

I still have to do the other bracket, so I can take better pics and put together a DIY when I'm done.

YoitsTmac

09-01-2018, 11:30 PM

any update on this now that I've already ordered poly bushings? because, I completely forgot about this.

Dave1027

09-03-2018, 10:45 AM

My concern with installing these spherical bushings is road noise isolation. I noticed more of it after I installed my poly bushings. How is it with these?

Also, if this is an improvement, why didn't the car come from BMW that way? There must be some trade off.

DeathTrap

09-03-2018, 12:07 PM

Compromise. Spherical bearings are more expensive than rubber. Rubber also isolates/absorbs shock better, which is what most non-enthusiasts would prefer. That's probably why BMW went that route.

I hope to install mine soon. I doubt I will be able to detect much of a difference in road noise being that my RTABs probably don't even work anymore.

ZHPizza

09-03-2018, 12:57 PM

Finally got them installed on both sides. What a bitch. The chamfered edge of the bearing inserts into the chamfered edge of the trailing arm and the damn thing just refuses to go in straight. I ended up sanding the chamfered edge on the bearing (where my finger is in the pic) to give a smoother transition and eventually got them on the 3rd try after that.

https://uploads.tapatalk-cdn.com/20180903/2794157634c0751ccf7ee5884ff947f7.jpghttps://uploads.tapatalk-cdn.com/20180903/7247498c9a98eec6522d7ae0e2f786f6.jpghttps://uploads.tapatalk-cdn.com/20180903/06628ea0f18202ea064550c51a9147de.jpghttps://uploads.tapatalk-cdn.com/20180903/624384cb33715f2992e9847b83ee4b36.jpghttps://uploads.tapatalk-cdn.com/20180903/b017a24ec0c01851adb518c4cce28d7b.jpghttps://uploads.tapatalk-cdn.com/20180903/b15db467d56fe22a7c80ee88407b676a.jpghttps://uploads.tapatalk-cdn.com/20180903/9faaf20faea2d21408756c5d7a8c5a0d.jpghttps://uploads.tapatalk-cdn.com/20180903/a49327ae1e378ff257e4b9f527cd3ffa.jpghttps://uploads.tapatalk-cdn.com/20180903/8cb0c0357a1f734bb48dbab90017d672.jpg

YoitsTmac

09-03-2018, 08:06 PM

So excited to hear driver feedback.

YoitsTmac

09-19-2018, 10:25 PM

any updates?

ZHPizza

09-20-2018, 12:19 AM

So excited to hear driver feedback.Ok it's going to be really difficult for me to describe and I muddied the results by introducing two variables at once. I replaced the outer control arm rubber bushing (lower) and bearing (upper) with new bearings at the same time as the rtab, so what was originally one spherical bearing and two rubber bushings is now three spherical bearings.

My current thoughts after driving it a couple times: some bumps (think dips in the road, expansion joints in a bridge) are smoother because the suspension is able to move up and down without the restriction of a rubber bushing, while others (think the front edge of a bridge section) hit LOUD through the rear frame. It's maybe 30-40% of the impacts I encounter that are the loud variety, and the sound clangs through the frame like a truck with overload springs. BUT I don't feel the clang any more than normal. Hell, the impact harshness may even be reduced over the OE rubber bushings. I've already noticed that I'm hitting railroad tracks with more speed, so that makes me think that it's handling bumps better.

As of right now, I hate the noise and am considering going back to the OE rubber, BUT I am going to wait until I get my new tires mounted. The current tires are stretched enough that the sidewall has little to no flex, so impacts are much harder than need be. I'm hoping that the wider, taller tires with sidewall flex will absorb some of the impact instead of sending the noise right into the frame.

Tldr the suspension moves like I always wanted it to but 30% of the bumps I encounter are obnoxiously loud with my stiff tires. Also not sure how much of that is due to the bushing>bearing swap in the lower outer position too.

Honestly, anything that you experience with these should be just like any of the other spherical rtab options (Turner, Bimmerworld, etc), so user reviews for those would apply.

san

09-20-2018, 05:17 AM

Ok it's going to be really difficult for me to describe and I muddied the results by introducing two variables at once. I replaced the outer control arm rubber bushing (lower) and bearing (upper) with new bearings at the same time as the rtab, so what was originally one spherical bearing and two rubber bushings is now three spherical bearings.

My current thoughts after driving it a couple times: some bumps (think dips in the road, expansion joints in a bridge) are smoother because the suspension is able to move up and down without the restriction of a rubber bushing, while others (think the front edge of a bridge section) hit LOUD through the rear frame. It's maybe 30-40% of the impacts I encounter that are the loud variety, and the sound clangs through the frame like a truck with overload springs. BUT I don't feel the clang any more than normal. Hell, the impact harshness may even be reduced over the OE rubber bushings. I've already noticed that I'm hitting railroad tracks with more speed, so that makes me think that it's handling bumps better.

As of right now, I hate the noise and am considering going back to the OE rubber, BUT I am going to wait until I get my new tires mounted. The current tires are stretched enough that the sidewall has little to no flex, so impacts are much harder than need be. I'm hoping that the wider, taller tires with sidewall flex will absorb some of the impact instead of sending the noise right into the frame.

Tldr the suspension moves like I always wanted it to but 30% of the bumps I encounter are obnoxiously loud with my stiff tires. Also not sure how much of that is due to the bushing>bearing swap in the lower outer position too.

Honestly, anything that you experience with these should be just like any of the other spherical rtab options (Turner, Bimmerworld, etc), so user reviews for those would apply.

Which tool did you use to replace the rear upper and lower control arm bushings?

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ZHPizza

09-20-2018, 06:46 AM

Which tool did you use to replace the rear upper and lower control arm bushings?

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I was able to do it with Spenser's Schwaben kit: https://www.ecstuning.com/b-schwaben-parts/schwaben-silent-block-tool-set/024979sch01a/

san

09-20-2018, 07:15 AM

I was able to do it with Spenser's Schwaben kit: https://www.ecstuning.com/b-schwaben-parts/schwaben-silent-block-tool-set/024979sch01a/

Thanks! I have a similar tool that I got from HF, wonder if that can do the job just as well.

Now that I think about it, I gave it to a friend over an year ago and haven’t taken it back. Hope he still has it.

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ZHPizza

09-20-2018, 10:21 AM

Here's a better summary of the difference these make, written by a guy on m3f:

The good:
Absolutely no wandering from the rear under acceleration (not including total loss of traction)
Throttle inputs have a much more direct effect on what you feel against your butt
The "bad":
You also feel stuff that causes fore and aft movement of the rear wheels (reflectors, pot holes, etc.) with your butt

Full thread here: http://www.m3forum.net/m3forum/showthread.php?t=584111

holyc0w

09-20-2018, 03:33 PM

Here's a better summary of the difference these make, written by a guy on m3f:

Full thread here: http://www.m3forum.net/m3forum/showthread.php?t=584111

If the noise was softer or gone would you plan on keeping them?

ZHPizza

09-20-2018, 03:48 PM

If the noise was softer or gone would you plan on keeping them?Yes 2000%. The noise is the only issue I have with them right now. I'm hoping to put about 400 miles on the car this weekend so I can get a better feel, then I'll install the spherical ball joints that I have for the FCABs, then put on the new tires.

These tires have transmitted a lot of nvh since I put them on but right now I like it since they amplify everything as I make changes in the suspension. Some people on m3f didn't notice any increase in nvh with the ball joint rtabs so it may not be noticeable with the right tires.

san

09-21-2018, 09:45 AM

Some people on m3f didn't notice any increase in nvh with the ball joint rtabs so it may not be noticeable with the right tires.

It could be because M3s have the rear upper and lower ball joints on the control arms from the factory instead of bushings like you had previously. So maybe the added harshness is from them and not the ball joint rtabs...

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ZHPizza

09-21-2018, 11:05 AM

It could be because M3s have the rear upper and lower ball joints on the control arms from the factory instead of bushings like you had previously. So maybe the added harshness is from them and not the ball joint rtabs...

Sent from my iPhone using TapatalkAbsolutely. I wish it would have been more convenient to test one variable at a time but I was in a rush to get everything done before an upcoming track night.

Reading through the m3f thread that I linked above would give good opinions on just the rtab change.

WOLFN8TR

09-23-2018, 08:43 AM

Next time you have your car up in the air, use a prybar to flex the rear trailing arm, you won't believe how much movement the rubber bushing allows!

yep, then imagine under power how much squirmy-squirmy the rear wheels are doing...

i once saw some on-board video of the rear wheels on a stock E46 M3 under load, in a corner... and you could actually see a good 10-15mm of axial movement in the wheel from the stock RTAB. crazy. think of the toe changes!

X2. I had bad OE RTAB's and noticed this when my car was all stock. I upgraded to RE Poly RTAB's and they made a big difference. Fast forward to headers and full exhaust, intake, engine tune etc. I can feel the rear end flex under power, it feels loose, normal city driving they are fine. I've been looking at the SDW or the new Turner RTAB's, expensive but I feel they are totally worth it.

RTAB's
http://www.m3forum.net/m3forum/showthread.php?t=584111

SDW RTAB's (https://www.fcpeuro.com/products/bmw-trailing-arm-monoball-kit-syncro-design-works-rtab#video0)

Turner RTAB's (https://www.turnermotorsport.com/p-555366-turner-motorsport-sealed-monoball-rear-trailing-arm-bushings-street/)

holyc0w

11-04-2018, 08:24 PM

Here's a better summary of the difference these make, written by a guy on m3f:

Full thread here: http://www.m3forum.net/m3forum/showthread.php?t=584111

I got the bimmerworld RTABs and I don't notice anything too harsh going on in the back. The problem is I've had a bunch of staff changed recently, so I'm not sure what contributes how. It does see a bit more noisy overall, though I think the main contributors are the poly differential mount and subframe bushings. Vibrations seem to be an insignificant difference. In some cases it seems that there is less vibration than before.

d-rod

11-04-2018, 09:20 PM

I got the bimmerworld RTABs and I don't notice anything too harsh going on in the back. The problem is I've had a bunch of staff changed recently, so I'm not sure what contributes how. It does see a bit more noisy overall, though I think the main contributors are the poly differential mount and subframe bushings. Vibrations seem to be an insignificant difference. In some cases it seems that there is less vibration than before.

I have the bimmerworld RTABs and it rides great etc on smooth highway roads, but anytime I hit anything even the reflectors that split lanes it’s pretty miserable. The problem here is the roads are not great so city driving suuucks!

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holyc0w

11-04-2018, 09:35 PM

I went over railroad tracks and it was surprisingly smooth.

ZHPizza

11-05-2018, 04:20 AM

I have the bimmerworld RTABs and it rides great etc on smooth highway roads, but anytime I hit anything even the reflectors that split lanes it’s pretty miserable. The problem here is the roads are not great so city driving suuucks!

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I went over railroad tracks and it was surprisingly smooth.I can echo both of these statements with my Moog bearings. Dips in the road, train tracks, etc are all super smoothed out with the bearings, but anything with a leading edge that puts a horizontal load on the rear trailing arm (where the rubber bushing would compress to allow the trailing arm to flex out of toe and absorb the impact) rattles through the frame. It's loud.

I'm wondering if the holes drilled in the body of the TMS unit would help dampen some of that impact if you filled them with rubber (or even better, fluid):

https://3a663eb0fef48c6d2d60-a88f8ebfcdb877ad223e888bfcb7f7ec.ssl.cf1.rackcdn.c om/1074895_x600.webp

Probably a fool's errand, though. I'd try it if they weren't so damn expensive.

holyc0w

11-07-2018, 09:02 AM

I can echo both of these statements with my Moog bearings. Dips in the road, train tracks, etc are all super smoothed out with the bearings, but anything with a leading edge that puts a horizontal load on the rear trailing arm (where the rubber bushing would compress to allow the trailing arm to flex out of toe and absorb the impact) rattles through the frame. It's loud.

I don't know which noise is coming from where, but I'm curious to see how things would be back on the rubber bushings. So far I can't say I would recommend this for a daily driver.

Vas

11-07-2018, 04:18 PM

Z4m with limiters is what I have installed.

I know most would not agree though.

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ZHPizza

11-07-2018, 05:46 PM

Z4m with limiters is what I have installed.

I know most would not agree though.

Sent from my Pixel 2 XL using TapatalkThanks for this. I spent the past two hours researching oe+limiters vs poly vs delrin vs spherical bearing and learned a ton. Just put in an order for the latest revision of the oe rtabs (z4m):

https://www.fcpeuro.com/products/bmw-trailing-arm-bushing-e36-e46-33326770817

And, from what I've gathered, the best option for limiters:

https://vorshlag-store.com/collections/bmw-e36-bushings-and-driveline-mounts/products/rear-trailing-arm-bushing-limiters-full-set

I really like the UHMW material that vorshlag uses for their limiters and would put it well ahead of any poly, delrin, or aluminum options. I have used a lot of these materials in industrial settings and was thinking that UHMW would be perfect for this application, so it's worth the price (to me) over the poly limiters that FCP packages with the bushings.

ZHPizza

11-07-2018, 05:51 PM

I should also mention that the spherical rtabs are AWESOME on the track and increased rear grip so much that I don't feel like I need an LSD anymore. It's actually quite a bit more difficult to get the car sideways and a bit of a buzzkill when you're tryna hoon.

I just think they transfer too much impact for street use.

slater

11-08-2018, 05:34 AM

I can echo both of these statements with my Moog bearings. Dips in the road, train tracks, etc are all super smoothed out with the bearings, but anything with a leading edge that puts a horizontal load on the rear trailing arm (where the rubber bushing would compress to allow the trailing arm to flex out of toe and absorb the impact) rattles through the frame. It's loud.

that's so weird. i don't have any of those issues with my bimmerworld ones.

cornercarver

11-08-2018, 05:43 AM

Thanks for this. I spent the past two hours researching oe+limiters vs poly vs delrin vs spherical bearing and learned a ton. Just put in an order for the latest revision of the oe rtabs (z4m):

https://www.fcpeuro.com/products/bmw-trailing-arm-bushing-e36-e46-33326770817

Are these the same RTABs as the E46 M3?

ZHPizza

11-08-2018, 07:24 AM

that's so weird. i don't have any of those issues with my bimmerworld ones.

You also have reasonably fitted wheels and tires. I'm runnin that stretch lyfe with no sidewall flex to take up some of the impact.

Are these the same RTABs as the E46 M3?

Yup

slater

11-08-2018, 07:38 AM

You also have reasonably fitted wheels and tires. I'm runnin that stretch lyfe with no sidewall flex to take up some of the impact.

true... but, 245/34/18's, they have less sidewall (0.2") than stock diameter. with my 17" x-ice winters, it actually feels perfect. :)

ZHPizza

11-08-2018, 08:45 PM

true... but, 245/34/18's, they have less sidewall (0.2") than stock diameter. with my 17" x-ice winters, it actually feels perfect. :)Exactly. The Growlour drove perfect on winter 17's + vincebar. I was hoping to drive it on the 18" summer tires but then you showed up with your 335i and we know how that drive went...

slater

11-10-2018, 06:53 PM

Exactly. The Growlour drove perfect on winter 17's + vincebar. I was hoping to drive it on the 18" summer tires but then you showed up with your 335i and we know how that drive went...

LOL. sorry to.... let you down? ;)

ZHPizza

11-15-2018, 08:08 AM

Update: I installed a fresh set of Lemforder rubber RTABS with Vorshlag limiters and drove the car this morning. It was dumping rain, so I didn't get to test the rear grip, but the ride is certainly improved. I believe I still have some excessive noise, which would point to the LCA bearing installed in place of the rubber bushing being the culprit. Will update this after more miles over the weekend.

BMWCurves

11-17-2018, 10:51 AM

Interested to hear your thoughts transitioning to the Z4M RTABs with the Vorshlag limiters, it's the same setup I have in the ol' derrière

ZHPizza

03-15-2020, 10:05 AM

Interested to hear your thoughts transitioning to the Z4M RTABs with the Vorshlag limiters, it's the same setup I have in the ol' derrièreRides like stock (duh) but I really miss the planted feeling of the sphericals. I'll eventually find a way to go back to them.

Galapolis

11-10-2020, 02:57 PM

I installed the Moog RTABs last week (thanks @ZHPizza for providing the tools and garage). Luckily I had the RTAB whisperer to help me with the install so it actually went faster than when I did the poly bushings. First, a few pics:

37452
37453
37454
37455

All I can say is WOW. I would have never imagined how huge the difference could be. This is up there with VANOS seals and the shorter diff. It literally completely transforms the car. The rear feels so much more comfortable. At first it feels soft but you quickly notice that it's really just compliant now. The car rides super smooth and is extremely planted. Wheel spin? What wheel spin? This is a budget LSD bro. No more inner wheel spin for me.

Transitioning into drifts is super smooth too (in the rain). In the dry, it doesn't really break loose anymore, but that's fine by me. Too much wear when you do that anyway. When I do get to go sideways in the rain, it's much more predictable, controllable and smoother.

AND NO MORE STUPID SQUEAK SQUEAK SQUEAK SQUEAK LIKE WITH THE POLY RTABS.

I haven't heard any noises over leading edges yet, but I'll keep an ear on it.

BMWCurves

11-10-2020, 03:07 PM

Moog?

t.er

11-10-2020, 03:12 PM

Yeah, Mightycarmods is selling these specifically for E46

moog (https://www.moogparts.ca/)

Galapolis

11-10-2020, 03:15 PM

Moog?

37458 + 37459 = 37461

BMWCurves

11-10-2020, 05:52 PM

Yeah, Mightycarmods is selling these specifically for E46

moog (https://www.moogparts.ca/)

Grassy ass, amigo

s14realm3

01-09-2021, 01:29 AM

ZHPizza

01-09-2021, 06:27 AM

Any link to Mightycarmods who sell these?
Also I see you had to sand down the MOOG bearings, what did you use? I am having a hard time getting thr MOOG to install in straight, keeps wanting to cock and jam up. Thx

Hey I saw your PM but wanted to answer here so everyone else had the info.

Reducing the diameter of the whole bushing was critical to getting a good fit. @Galapolis can elaborate but I think we ended up going at it with a file to try to take that diameter down more. Just, you know, don't take too much off. There's more pics of how I chucked it up in the drill on the e46f thread linked in the first post.

Also a very good idea to put them in the freezer overnight so they shrink down a bit before trying to install. We didn't have time for that so just threw them in a bucket of ice water for half an hour and it helped. Just make sure you dry them off well and apply a little antiseize to keep them from being a permanent install.

s14realm3

01-09-2021, 01:38 PM

Did my Toyota spherical bearing install today. After some dremel sanding of rhe bearing housing, I was able to get the bearing pressed in. All is good, going to alignment shop Monday. Btw- this is on my e83 X3, uses the same RTAB as e36 and e46. This isn't a plug and play install but the modifications isn't that bad now that I know what to do. Thanks guys for the write ups and pictures in this thread. For some reason, I do not have the abilities to attach pictures in my post or I would add some of mine in this thread to help others.

t.er

08-11-2021, 08:09 AM

Thought I should post my experience here. I've already posted a bunch of this in the "What have you done" thread but all that will get lost, so here it is. Being the cheap-ass I am I rented the free ball joint press tool from Crappy Tire (Autozone for folks down south) and also because of this video (https://www.youtube.com/watch?v=_A6SqbMowgE), which made it look so easy. However the area to press on is so much smaller than other commercially available sphericals, which limits the attachment pieces you can use.

It is possible to use that tool (https://www.canadiantire.ca/en/pdp/oemtools-ball-u-joint-press-set-1250043p.html#srp), but I found you will also need to rent the expansion kit (https://www.canadiantire.ca/en/pdp/oemtools-master-ball-joint-installer-remover-adapter-set-1250078p.html), which has more cups/tubes. All in all, it does work but really sucks to use, for a few reasons.

First is the bent tool, which caused it not to press in straight. Maybe it's just mine, and I think the picture enhances the crookedness, but you can see the top not being parallel with the bottom:

https://i.imgur.com/bo0ZY3El.png

So you may think you can just rotate the tool every few turns to even out the crookedness. But with the trailing arm so close to the body, you don't have a lot of freedom with that. So I just did this:

https://i.imgur.com/cJANQtAl.png

Another thing is that even with the optional cup kit, there were situations where the combination of all the attachment pieces meant it wouldn't fit within the press. So I had to get creative:

https://i.imgur.com/KT6wnScl.png

As for fasteners, it was mentioned here already but you need M14 x 75 mm or 9/16" x 3" bolts. I didn't want to use imperial fasteners and M14 bolts are quite difficult to come by - if you are in Canada you can order from Spaenaur (https://spaenaur.com/), which like McMaster-Carr but without the awesome website. Or just order from McMaster. Dorman also sells these fasteners, the bolt is 428-875 (https://www.dormanproducts.com/p-11462-428-875.aspx), the nut is 433-014 (https://www.dormanproducts.com/p-7739-433-014.aspx), and the washer is 437-314 (https://www.dormanproducts.com/p-3228-437-314.aspx).

Lastly, just as a precaution put a towel between your brake line and the upper CA. Maybe it's fine with stock lines, but I tore into the outer liner on my Stoptechs, so I had to buy a pair of rear brake lines to replace them. Oh and make sure you remove the clip that strain reliefs the brake line or it will have some tension holding the trailing arm up.

https://i.imgur.com/6xTVvuFl.png

https://i.imgur.com/SEQbIcil.png

Anyways, a lot of hype around these budget sphericals so my expectations are high!