Front Control Arm Ball Joint Boot Repair

[maupineda]

I searched up and down without anything specific to our suspension architecture relative to a dust boot repair/replace on the front control arms.

While removing the front knuckles to refurb them I damaged the boot on the passenger side, I was very reluctant to spend 300 on a control arm just for a stupid rubber boot. So I came up with the idea of sourcing just the ball joint, which is available for non M control arms from Lemforder to harvest the boot.

bloddy hell, those rings are a PITA to remove, but is doable after watching some YT videos on how to remove these boots on some Japanese models.

the image below shows the naked ball joint.

I will post photos of the boot and clips that hold them in place.

[cobra]

When I replaced the ball joints on my tacoma, the new ones came with a little roll of safety wire and they instructed you to give it 2 wraps and tuck in the twisted end where it won't be at a pinch/bend point. Seems to hold up alright.

[George Hill]

Is that an E36 strut? *Edit, I saw your other post, its a Z4.

Either way I feel your pain, but seeing that blue M/// tag makes me think this arm is original and at 20yrs old +/- its probably a bit tired anyways. If that ball joint moves freely even with out any discernable play I'd consider replacing it while you are in there.

[4getr34]

Nice. Also can you share some of the videos you watched? I need to do this.

[maupineda]

Received the donor ball joint and removed the boot.

The blue rings are the originals. the larger ring is called a retainer ring, and is like the ring of a key chain, the smaller ring is more of a snap ring that is pretty tough. I used a shallow pick to just get it behind the ring and pry it out carefully. I chose not to install this smaller ring as I am sure I would end up punching a hole on the new boot trying to install that thing on. instead I got another retainer ring from McMaster, it is basically identical to the larger one but smaller, and lucky me McMaster happened to have one of identical diameter.



You can see below the retainers. And the tools I used. The zip ties are to pull the ring apart to wind it on and not damage the boot. When I receive the small ring tomorrow from McMaster will share the photo



I trailed installing the torn boot onto the new ball joint to learn the process. The ring retainer that looks like a key chain ring is easy to install, just wind/unwind it around with the help of pick. You can also fish in a zip tie to spread the ring apart and start unwinding out.

[sapote]

Received the donor ball joint and removed the boot.

Is the new donor ball joint OEM for the stock control arm or aftermarket part?
The larger bottom ring is required to keep the boot from popping out, and the top ring is only to keep the water and dust out, so I think looping a copper wire 2 turns and twist the ends will work as an easy substitute.

[maupineda]

The ring came in. Exactly the same size but much easier to install.

[sapote]

The ring came in. Exactly the same size but much easier to install.

does the blue ring always has the gap or this was created when you tried to spread it out during removal? when installed I would expect the gap is minimal otherwise this can lead to water got in. (Same for the brake caliper dust boot ring which is not a complete circle allowing water to get in at the ring gap, but I always added some grease inside the boot to seal off this area.)
I like the key ring style ring better as it creates a complete uniform 360 deg pressure for a good seal.

[4getr34]

Is the new donor ball joint OEM for the stock control arm or aftermarket part?

Same question - also whats the part number for McMaster?

[maupineda]

Job done!!!



to answer the questions above… when installed the blue ring does not have gap (before removing), i actually think I bent it a bit during the removal process. The same happened to the original ring which was yellow. That was one of the reasons I replaced it. You have to spread it open some!

the McMaster part is

https://www.mcmaster.com/product/92347A190

ones installed both rings were perfectly circular

[4getr34]

nice! is this what ball joint you bought?

https://www.bimmerworld.com/Suspension-Steering/Control-Arms/Inner-Ball-Joint-Meyle-HD-E46-Z4-3160104305HD.html

[maupineda]

nice! is this what ball joint you bought?

https://www.bimmerworld.com/Suspension-Steering/Control-Arms/Inner-Ball-Joint-Meyle-HD-E46-Z4-3160104305HD.html

no, that is the inner. you need the outer.

https://www.fcpeuro.com/products/bmw-ball-joint-front-outer-e36-hd-31126758510my

[davidinnyc]

This thread couldn’t have come at a more perfect time. I decided to swap back to stock suspension on the vert and absolutely obliterated the boot on the driver’s side… ordered parts!

[4getr34]

This thread couldn’t have come at a more perfect time. I decided to swap back to stock suspension on the vert and absolutely obliterated the boot on the driver’s side… ordered parts!

nice. try to document and report back! i will do this in a few weeks

[enjoy_m3]

I assume your ball joint still have good resistance like a new ball joint? FYI, I believe z4m control arm part number is the same as zhp. Lemforder makes an HD version with replaceable ball joints. Too bad the e46 m3 doesn't have a version.