Rear Bearing Noise

E28 technical advice asked and given! Troubleshooting, modifications and more.
Post Reply
Syndrome
Posts: 128
Joined: Nov 23, 2021 3:46 PM
Location: DC

Rear Bearing Noise

Post by Syndrome »

Hey all. The left rear wheel bearing on my M5 is beginning to make some noise and I’m gearing up to swap it out. I understand this might be nightmarishly hard to do and requires special tools. That being said, is it possible to find another rear swing arm with a new bearing and install it on my chassis instead? Are all E28 models the same back there as the M5? Advice? Thanks you!
Blue Shadow
Posts: 10195
Joined: Feb 12, 2006 12:00 PM
Location: SE PA

Re: Rear Bearing Noise

Post by Blue Shadow »

The trailing arm changed in 9/86 so you need a later one to do the swap. you can go in with all new bushings and such.
Mike W.
Posts: 26872
Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: Rear Bearing Noise

Post by Mike W. »

Blue Shadow wrote: Mar 19, 2023 7:34 PM The trailing arm changed in 9/86 so you need a later one to do the swap. you can go in with all new bushings and such.
That's right. I think later ones had braces and there was a change in the ABS sensor. You can run an early or late arm, but you need the correct ABS sensor. The two are compatible electrically, but a different form factor/shape, so they don't interchange.

When I had a wheel bearing go on my '85, cars were plentiful at P and P. I picked the newest eta figuring it would have the least wear, only to find out the sensor didn't go in. Back in the day... $15 for the arm and $5 for the sensor. Those days are long gone.
Syndrome
Posts: 128
Joined: Nov 23, 2021 3:46 PM
Location: DC

Re: Rear Bearing Noise

Post by Syndrome »

Thanks. Well, it sounds like a lot of work in any case. How much can I expect to spend to have a shop replace my bearing? Thanks again.
adam_poll
Posts: 206
Joined: Jul 23, 2014 8:19 PM
Location: Kitchener, Ontario, Canada

Re: Rear Bearing Noise

Post by adam_poll »

There's nothing complicated about replacing a rear wheel bearing, the bearing is just pressed in there really well so it is difficult to remove without the proper tools. A shop should have those tools though to do it on the car but I'd still expect a couple of hours by the time they remove the brakes, halfshaft etc. to get at it. I think this is the better route to go over hoping a used trailing arm is in better shape overall.

This could be a good time to look at rear brakes, halfshafts (or just the boots), diff seals and that wheel bearing on the other side if you want to go all out.
Syndrome
Posts: 128
Joined: Nov 23, 2021 3:46 PM
Location: DC

Re: Rear Bearing Noise

Post by Syndrome »

Agreed. Thank you!
Post Reply