1998 M3 Control Arms upgrade

[gtdan]

Hello everyone,
I have read the other threads that are couple of years old in regards to 1998 M3 control arm upgrade.

I am in need of new control arms for my 98 M3 coupe.
I found this on bimmerworld, it says control arms are non M but then it fits the M with those bushings perfectly it says. Has anyone tried these ?

https://www.bimmerworld.com/Suspensi...-M3-96-99.html

Any other recommendations for 98 M3 control arm and bushing upgrade?

Some people installed Meyle HD control arms in the past. How it’s been after few years?

[aeronaut]

Using non-M arms with the offfset bushings is what the 95 M3 had, and is a common (cost savings) install on the 96+.
I don't peronally care for the Powerflex bushing design in that location, so consider other offset bushings.

You can also replace just the ball-joints in your current 96+ arms. Several threads on that, and if you don't have the press to remove/install the ball joints, most any auto shop or machine shop can do it.

[Braymond141]

Refresh or replace exactly what you have. A lot of “upgrades” are actually downgrades.

[Nova1]

Having just gone from powerflex FCAB back to OE centered bushings in my 99 I can tell you I would never put poly anything back in my car again. The car drives like a dream, best it’s felt in years.
New meyle control arms and control arm bushings for me.

[Braymond141]

I'd recommend sticking with original Lemforder arms (only available from BMW) if you don't have the tools to replace the balljoints yourself. Avoid off brands.

[bluptgm3]

Using non-M arms with the offfset bushings is what the 95 M3 had, and is a common (cost savings) install on the 96+.

You can also replace just the ball-joints in your current 96+ arms. Several threads on that, and if you don't have the press to remove/install the ball joints, most any auto shop or machine shop can do it.

It is important to note that the E30, non-‘M’ E36, and 1995M3 FLCAs are the same geometry.

Internet lore has been that E30 FLACs have smaller inner BJs. True? IDK….

Non-‘M’ E36 FLCAs have a rubber isolated outer BJ.

Aftermarket non-‘M’ E36 FLACs such as Meyle HD have a solid outer BJ, and have been used on both the 1995M3 and 1996+M3, both installations requiring 1995M3 offset FLCABushings.

While the 1995M3 and 1996+M3 FLCAs are not intended as having replaceable BJs, many people have done so with (Lemforder) E30 BJs.


The M3 FLCA and King Pin was redesigned for the 1996+M3. The 1996+M3 FLAC has less ‘hook’ at the outer ball joint location.

[RBNetEngr]

I have those exact poly FCABs on my ‘95 M3 and I don’t have any issues with them. And the installation procedure is so much simpler than the factory bushings, and having to deal with getting the control arm rotational position properly oriented in the bushing before the lube stops allowing it to rotate.


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[gtdan]

Having just gone from powerflex FCAB back to OE centered bushings in my 99 I can tell you I would never put poly anything back in my car again. The car drives like a dream, best it’s felt in years.
New meyle control arms and control arm bushings for me.

Why is that?

[Braymond141]

Why is that?

Because polyurethane is garbage in most use cases.

[Nova1]

Why is that?

If BMW had engineered the car with polyurethane bushings, I would use them. But they didn’t.

I’m not opposed to modification or trying something new with your car. I’ve done it. But this car was designed to function a certain way and that’s how I want to enjoy it now.

[RBNetEngr]

You could also argue that BMW engineered it with rubber bushings rather than polyurethane because rubber bushings are cheaper to produce.

There are good and proper uses for polyurethane bushings. In the case of FCABs, where the control arm motion is purely rotational, with a very small amount of vertical or horizontal movement by the control arm end in the FCAB, the poly bushing does everything that the rubber bushing does, but they are easier to install and they do not provide any control arm bushing preloading when the arm moves as the wheel travels up and down.

On the other hand, the RTAB bushings experience much more than pure vertical, rotational motion, and polyurethane bushings are not well-suited there. I replaced my RTABs with sealed spherical bearings (from Bimmerworld, although several vendors sell them). The spherical bearings provide full range of motion of the rear control arms, in all directions. And they also have the advantage of easy installation compared to the rubber RTABs, which need to have the bracket angles set properly prior to bracket installation, so that the RTABs are not preloaded at loaded ride height. The spherical bearing just rotates to accommodate the positioning of the trailing arm, so there is no possibility of preload on the RTABs.


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[blckstrm]

You can also replace just the ball-joints in your current 96+ arms. Several threads on that, and if you don't have the press to remove/install the ball joints, most any auto shop or machine shop can do it.

I'd recommend sticking with original Lemforder arms (only available from BMW) if you don't have the tools to replace the balljoints yourself. Avoid off brands.

My experience has been what Brett recommends. This is NOT as easy as it would seem. I gave my FCAs to a shop and they screwed it up three times. I'd recommend getting the equipment to do it yourself.

I say this all the time, but no snot-nosed grunt at a shop like this cares about your stuff more than you do.

Unless you can find a place like Brett's AND are willing to pay for it, you're better off doing this stuff yourself.

You could also argue that BMW engineered it with rubber bushings rather than polyurethane because rubber bushings are cheaper to produce.

There are good and proper uses for polyurethane bushings. In the case of FCABs, where the control arm motion is purely rotational, with a very small amount of vertical or horizontal movement by the control arm end in the FCAB, the poly bushing does everything that the rubber bushing does, but they are easier to install and they do not provide any control arm bushing preloading when the arm moves as the wheel travels up and down.

On the other hand, the RTAB bushings experience much more than pure vertical, rotational motion, and polyurethane bushings are not well-suited there. I replaced my RTABs with sealed spherical bearings (from Bimmerworld, although several vendors sell them). The spherical bearings provide full range of motion of the rear control arms, in all directions. And they also have the advantage of easy installation compared to the rubber RTABs, which need to have the bracket angles set properly prior to bracket installation, so that the RTABs are not preloaded at loaded ride height. The spherical bearing just rotates to accommodate the positioning of the trailing arm, so there is no possibility of preload on the RTABs.


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I've done the same front and rear, and PERSONALLY I love it. But I acknowledge it's only the right move if sharpness is what you're going for. If you're not the type to be running a near-zero-toe alignment, it may not be what you're after.

[aeronaut]

My experience has been what Brett recommends. This is NOT as easy as it would seem. I gave my FCAs to a shop and they screwed it up three times. I'd recommend getting the equipment to do it yourself.

I say this all the time, but no snot-nosed grunt at a shop like this cares about your stuff more than you do.

Unless you can find a place like Brett's AND are willing to pay for it, you're better off doing this stuff yourself.



I've done the same front and rear, and PERSONALLY I love it. But I acknowledge it's only the right move if sharpness is what you're going for. If you're not the type to be running a near-zero-toe alignment, it may not be what you're after.

Jebus. Of course don't take a bag of parts to the dealer or NTB and ask them to assemble. Find an indepedent shop that has a press and uses it. or an actual machine shop. And know what to tell them to do (5 min of searching this forum shows that).
And poly is not "garbage in most use cases". But yes, there are always trade-offs. For off-set LCAB's, on a street car, I would recommend OEM style.

[blckstrm]

Jebus. Of course don't take a bag of parts to the dealer or NTB and ask them to assemble. Find an indepedent shop that has a press and uses it. or an actual machine shop. And know what to tell them to do (5 min of searching this forum shows that).
And poly is not "garbage in most use cases". But yes, there are always trade-offs. For off-set LCAB's, on a street car, I would recommend OEM style.

Of course this wasn't a dealer or NTB. But they cut a boot and mushroomed the bottom plate on the other, and then I had to swap the boot myself and get the replacement for the mushroomed one.

And then even though they looked fine on the second try, they were rattling after 10k miles. And the shop was MAYBE $50 cheaper than buying my own press at harbor freight.

And I have had this kind of thing happen with almost everything I have had ANYONE do on any of my cars. If you want something done right...

[TostitoBandito]

Yeah I'd agree that the control arm ball joint swaps are best DIY'd. I tried to find a shop when I was doing mine, but couldn't find any that I was confident would do it exactly right (or were willing to at all). It's not like it's complicated, but there are a few things you have to do correctly and if this isn't something they've seen before they won't have a clue. The big harbor freight press works fine if you can buy or borrow one.

Also, on poly bushings, similar to blckstrm I'm happy with mine. I did a lot of research prior to deciding what to do and came to the conclusion that I would go poly everywhere except the RTAB's which would be OEM plus limiters. The "feel" you get is not for everyone (I like it, and already had a fairly stiff suspension), but the poly does fine mechanically everywhere except RTAB's, which I wouldn't really recommend anyone use poly on (spherical/monoball or OEM).

[Braymond141]

Jebus. Of course don't take a bag of parts to the dealer or NTB and ask them to assemble. Find an indepedent shop that has a press and uses it. or an actual machine shop. And know what to tell them to do (5 min of searching this forum shows that).
And poly is not "garbage in most use cases". But yes, there are always trade-offs. For off-set LCAB's, on a street car, I would recommend OEM style.

Nah, it is. Especially here.

[Steve1998]

Count me in the anti-poly camp. There is no reason to use poly in any application. I did not like them in the LCAB. They felt unnatural and there was no great difference in sharpness. It is a given they are terrible for the RTAB. Solid is superior for the subframe. You should never change differential bushings from rubber on a street car. No use for poly.

[sfcarguy]

What's the consensus on the BW trackCAB or monoballs for the FCABs?

[Johal E32]

What's the consensus on the BW trackCAB or monoballs for the FCABs?

Don't do it if you have a street car. It is acceptable for a track only car

[RBNetEngr]

What's the consensus on the BW trackCAB or monoballs for the FCABs?

They work great. I have them on my car, as does blckstrm. No increase in NVH by adding them.


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[blckstrm]

They work great. I have them on my car, as does blckstrm. No increase in NVH by adding them.


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I think he's asking about FCABs, not RTABs. But I wouldn't be opposed. I have Delrin FCABs and I like them. The delrin FCABs are not an NVH contributor (nor are the RTAB monoballs).

I was given my FCABs from a friend's race car when he upgraded to E46 arms. The downside of delrin or poly seems to be wear / durability, so when these get loose I'll probably go to those trackCAB monoballs on the front, too. The rear monoballs made a huge difference, but I'm not sure how much the front added. But I'm hesitant to go back. I don't mind replacing these every 5-10 years. We'll see how long it takes the delrin to get loose, then we'll try the monoballs and compare.

[jayjaya29]

What's the consensus on the BW trackCAB or monoballs for the FCABs?

Adds loads more feedback to the steering feel without much of an NVH penalty. Although everyone's NVH threshold is different.

[bluptgm3]

Adds loads more feedback to the steering feel without much of an NVH penalty. Although everyone's NVH threshold is different.

I recall being at a TCKline Double Adjustable CO installation Tech Session just south of Seattle, back 10-15 years ago. TC himself was here, and stated that in terms of camber plates and FLCABs, you can do just about anything you want up front with out suffering (much) NVH penalty. The rear, RTAB location is however a much different story as you are seated just above that joint.