Are Front Control Arm Ball Joints Replaceable?

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songzunhuang
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Are Front Control Arm Ball Joints Replaceable?

Post by songzunhuang »

It looks like my control arm bushing are worn and need replacement. Also a few of the boots for the ball joints are compromised. Is it possible to replace the ball joint and bushings and keep the original steel arms?

Why would I want to do such a thing? Well, some of my control arms are cast with a nice BMW letters(see photo below) and I think it would be cool to keep them instead of replacing them with unmarked aftermarket units.
Nice BMW OEM upper control arms.
Nice BMW OEM upper control arms.
Control Arms.png (953.49 KiB) Viewed 2178 times
I know it can be a pain in the butt to do this instead of replacing with new units, but is it possible and has anyone done this? Thanks for any info.
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Ralph in Socal
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Re: Are Front Control Arm Ball Joints Replaceable?

Post by Ralph in Socal »

You may be able to replace the boots if the joints are still good.

Replacement aftermarket control arms may last as long as the life left on your bmw units 😆

Good luck Song

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Re: Are Front Control Arm Ball Joints Replaceable?

Post by songzunhuang »

Ralph in Socal wrote: Wed Mar 16, 2022 6:37 pm You may be able to replace the boots if the joints are still good.

Replacement aftermarket control arms may last as long as the life left on your bmw units 😆

Good luck Song

Ralph
Good to hear from you Ralph!

I don't think I'd just replace the boots. That seems like an exercise in futility. Of course trying to save the original arms may be an exercise in futility, but I thought I'd check before taking the leap with all new arms. I see a lot of replacement bushings available. Does this imply that the ball joints last way longer than the bushings?

Still, I appreciate the quick input. Still doing my research before pulling the trigger on new arms.
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Re: Are Front Control Arm Ball Joints Replaceable?

Post by jps635 »

Should be able to - just need to find someone to do it. I did this (not me personally) no too long ago witch my centre drag link as the RHD versions are very scarce now. But consider replacing the oem steel for oem alloy. From memory the e39 or e34 lc arms are a direct swap.
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Re: Are Front Control Arm Ball Joints Replaceable?

Post by 86_6series »

Looks like #'s 5 & 10 ball joints are not replaceable.

https://www.realoem.com/bmw/enUS/showpa ... Id=31_0016
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Re: Are Front Control Arm Ball Joints Replaceable?

Post by Ralph in Socal »

The Ball Joints do last much longer than the bushings so lots of replacement bushings available. BMW does not supply replacement ball joints so aftermarket is the only option.

Test the ball joint while installed by turning the steering from side to side while holding your hand on the joint. A good joint will travel through the turn without any roughness, bumping, jumping or noise. Do the test with the suspension in the air and while it's loaded on the ground. Any roughness in the joint is a sure sign of wear.

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Re: Are Front Control Arm Ball Joints Replaceable?

Post by songzunhuang »

Appreciate everyone's input.
During my lunch break today, I jacked up and crawled under the car to check things out for myself. My lower control arm ball joints are questionable and the dust boots are toast. The upper control arms (sometimes called thrust arms) seem to be in decent shape, although the passenger side dust boot is severely compromised. Curiously, the driver side ball joint dust boot is a red color while all others are black. I wonder if it's been replaced before.

Here's what things looked like on the driver side. The upper ball joint dust boot looks very different from the rest. I wonder if it's been replaced before? Interestingly, the bushing (not shown) look greenish in color. This side may have been serviced before.
Upper ball joint dust boot looks different.
Upper ball joint dust boot looks different.
Driver BallJoints.png (1.29 MiB) Viewed 2117 times
The passenger side arms both definitely needs service. Both ball joint dust boots are toast.
Both ball joint dust boots are toast.
Both ball joint dust boots are toast.
Passeenger BallJoints.png (1.31 MiB) Viewed 2117 times
So I have order 2 new lower control arms from FCP Euro. I got the aluminum upgrades. It says they were stock on the M6.
https://www.fcpeuro.com/products/bmw-co ... inumkit-my

Now, I grabbed the upper arms and pulled them back and forth very hard. I couldn't detect any play at all. However, the bushing on the passenger side looks to be original. It's got "patina".
Upper arm bushing looks original.
Upper arm bushing looks original.
Bushing.png (855.25 KiB) Viewed 2117 times
I think I can save the upper arms. I did find some interesting polyester replacement ball joint dust covers from a vendor on eBay. https://www.ebay.com/itm/303262513301

So I got those too. I'll replace the dust covers and maybe at a later date I'll replace the bushings too. So, one step closer to eliminating the shimmy I feel around 50-60mph.
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Re: Are Front Control Arm Ball Joints Replaceable?

Post by Ralph in Socal »

Best upgrade for the lower control arms are e31 (8 series) as they're aluminum with needle bearings instead of a bushing.

Those thrust arm bushings with the green inserts are aftermarket HD type. I think Meyle and could be E32 fitment. Get a measurement of the bushing thickness.

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Re: Are Front Control Arm Ball Joints Replaceable?

Post by rhanley 635csi89 »

Song, you want to reconsider and replace all the components at one time. You'll need a wheel alignment. Bottom line, you'll have a better ride, save time and save a little money in the long run. Roger
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Re: Are Front Control Arm Ball Joints Replaceable?

Post by songzunhuang »

rhanley 635csi89 wrote: Fri Mar 18, 2022 12:13 pm Song, you want to reconsider and replace all the components at one time. You'll need a wheel alignment. Bottom line, you'll have a better ride, save time and save a little money in the long run. Roger
Understood. I've already got stuff coming (see previous message) and I'll get an alignment once it's all done. I'll at least replace the dust boots for the uppers if the balls are still good and then get some new bushings on both sides.

Never heard of the needle bearing upgrade Ralph mentioned. More to explore.
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Re: Are Front Control Arm Ball Joints Replaceable?

Post by TimU »

Ralph in Socal wrote: Fri Mar 18, 2022 3:21 am Best upgrade for the lower control arms are e31 (8 series) as they're aluminum with needle bearings instead of a bushing.
They're also significantly more expensive, and don't appear to be available as a Meyle part. Lemforder and BMW OEM only.

Pelican parts pricing, at the time of writing:

E24 Front Lower Control Arm (Steel) Right (31121139992)
E24 Front Lower Control Arm (Steel) Left (31121139991)
- US$102.75 Lemforder
- US$51 Meyle

E28 M5/E24 M6 Front Lower Control Arm (Aluminium) Right (31121139988)
E28 M5/E24 M6 Front Lower Control Arm (Aluminium) Left (31121139987)
- US$142.25 Lemforder
- US$74.25 Meyle

E31 Front lower control arm (Aluminium) Right (31121138478)
E31 Front lower control arm (Aluminium) Left (31121138477)
- US$210.75 Lemforder
- N/A Meyle
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