[joe__]

I just bought new tires but the shop said they could not perform an alignment due to a worn control arm bushing. Yesterday I went to the dealer, purchased a new control arm with the bushing installed (part number 31126768984) and installed it without issue.

I was planning on going to have the alignment done tomorrow but after talking to a friend he suggested that I replace both control arms at the same time. Is this necessary? I pried on both arms before replacing them and the only one that had excess play was the one I subsequently replaced (passenger side).

Any opinion on this?

Car is a 2007 328XI.

[woodpecka]

I think you should do both if you think keeping the car for ~2 years. The second one should fail before this.

Suspension just like brakes should always be done in pairs, you don't just replace 1 rotor do you?

1 side of the car is going to have a brand new bushing, the other one with XXX miles that's soon on its way out.

You have to tighten the bushing (inner part of the arm that connects to the subframe) while the suspension is loaded, otherwise its going to wear out in a few thousand miles again.

If you didn't do this you can have the shop loosen and retighten the bolt while its on the alignment rack its a bit of a pain to do at home.

And if you brought the arm over the counter you overpaid, you can find them online for much cheaper, a lot of guys on here upgrade to the M3 arms which have better bushings, TRW branded vs OEM essentially the same part for a lot less money.
ECStuning.com is your friend, at this point in your case I would just order a OEM non-M3 arm for the other side.

[joe__]

Originally Posted by index1489

Suspension just like brakes should always be done in pairs, you don't just replace 1 rotor do you?

1 side of the car is going to have a brand new bushing, the other one with XXX miles that's soon on its way out.

You have to tighten the bushing (inner part of the arm that connects to the subframe) while the suspension is loaded, otherwise its going to wear out in a few thousand miles again.

If you didn't do this you can have the shop loosen and retighten the bolt while its on the alignment rack its a bit of a pain to do at home.

And if you brought the arm over the counter you overpaid, you can find them online for much cheaper, a lot of guys on here upgrade to the M3 arms which have better bushings, TRW branded vs OEM essentially the same part for a lot less money.
ECStuning.com is your friend, at this point in your case I would just order a OEM non-M3 arm for the other side.

Thanks for the tip on retightening, did not know that. I'll see if there's anyway I can squeeze in and do it at home but like you said... it'll be hard.

I considered the M3 arms but was told that XI has a different setup?

[09E90utah]

Originally Posted by index1489

Suspension just like brakes should always be done in pairs, you don't just replace 1 rotor do you?

1 side of the car is going to have a brand new bushing, the other one with XXX miles that's soon on its way out.

You have to tighten the bushing (inner part of the arm that connects to the subframe) while the suspension is loaded, otherwise its going to wear out in a few thousand miles again.

If you didn't do this you can have the shop loosen and retighten the bolt while its on the alignment rack its a bit of a pain to do at home.

And if you brought the arm over the counter you overpaid, you can find them online for much cheaper, a lot of guys on here upgrade to the M3 arms which have better bushings, TRW branded vs OEM essentially the same part for a lot less money.
ECStuning.com is your friend, at this point in your case I would just order a OEM non-M3 arm for the other side.

Wouldn't an easy way at home be to put an extra jack under the rotor then load it so it's slightly off the jack stand? You should now have the room with the tire removed. Or is this too unsafe?

Yea some people do this, you measure and jack up the rotor to ride height, use a piece of wood to not damage the rotor and be careful not to jack it up too much where the car starts coming off the main jack.

Even if you measure carefully its not the most precise way of doing it, but much better then bolting down the bushing with the arm at full droop.