Excessive road noise on passenger side.

javis20 · Post by **javis20** » Fri Mar 17, 2023 12:40 am

MikeyH wrote: ↑Thu Mar 16, 2023 12:14 am I think it’s the seat belt wind noise, I noticed that.

Yea, it seems like the seatbelt retractor hole is directly ported to the wheel well.

javis20 · Post by **javis20** » Wed May 03, 2023 1:11 am

Well I got to the bottom of the excessive noise problem. Apparently the rear tires are cupped on the inside edge, the right rear wheel is bent and the differential is worn and leaking. At this point I'm planning to just buy a new rear differential for $2000 and have an indie install it. In the mean time I'll find a 2nd hand wheel before replacing the rear tires.

B21 · Post by **B21** » Wed May 03, 2023 9:49 am

javis20 wrote: ↑Wed May 03, 2023 1:11 am Well I got to the bottom of the excessive noise problem. Apparently the rear tires are cupped on the inside edge, the right rear wheel is bent and the differential is worn and leaking. At this point I'm planning to just buy a new rear differential for $2000 and have an indie install it. In the mean time I'll find a 2nd hand wheel before replacing the rear tires.

Quite a combo

Maybe get a second hand diff and get a LSD put in for the same money ?

javis20 · Post by **javis20** » Wed May 03, 2023 12:04 pm

What's an LSD?

Chippie · Post by **Chippie** » Wed May 03, 2023 12:40 pm

javis20 wrote: ↑Wed May 03, 2023 12:04 pm What's an LSD?

Not sure man, think it’s something from the 60’s
Limited slip differential

javis20 · Post by **javis20** » Wed May 03, 2023 6:42 pm

I'm trying to decide between buying a new differential ($2050) or picking up a used one for $550. The used one has 39k miles on it. Any advise?

B21 · Post by **B21** » Wed May 03, 2023 6:59 pm

javis20 wrote: ↑Wed May 03, 2023 6:42 pm I'm trying to decide between buying a new differential ($2050) or picking up a used one for $550. The used one has 39k miles on it. Any advise?

What model E89 do you have ?

javis20 · Post by **javis20** » Wed May 03, 2023 7:39 pm

2011 z4 auto trans. 3.0i. Differential part number 33107576667. Basically wondering if these differentials are problematic and a used one would also be destined to fail at 60k miles. If so, I would hold my nose and buy a new one.
Otherwise, it would be preferred to get a used one. Considering the indie shop found my rear right wheel bent, and both rear tires need to be replaced to pass july state inspection.

B21 · Post by **B21** » Wed May 03, 2023 8:45 pm

The diffs are usually pretty bulletproof…suggest you get a used one..check it on arrival and fill it with fresh oil

Chippie · Post by **Chippie** » Wed May 03, 2023 9:19 pm

javis20 wrote: ↑Wed May 03, 2023 7:39 pm Considering the indie shop found my rear right wheel bent, and both rear tires need to be replaced to pass july state inspection.

I suspect that at some point it’s had a whack on that right rear wheel, which has possibly damaged the gears in the diff and thrown the wheel alignment out.

Christopher72 · Post by **Christopher72** » Thu May 04, 2023 2:43 pm

It's too expensive to fix on mine -- I will have to live with it. I checked the suspension, tyre, wheel, bearing, seat belt, trim, differential, brakes, etc. After replacing everything with new parts, lube and such... Still the noise. It's driving me crazy but like Tinnitus, it probably can be ignored as background noise if you work at it. So, I checked into my doctor for a medication solution. He told me that my hearing was fine.

So I tried to think outside-of-the-box... and the noise origination started to become clear. After that moment of clarity, I almost wept in despair. This wasn't something I could afford to fix -- It's not something that can be ordered from Germany or Latvia. I realized that the noise originates from my wife commenting from the passenger seat that I focus too much on the car. And she's too expensive to replace....

javis20 · Post by **javis20** » Fri Jun 23, 2023 3:47 am

Well I found a 2nd hand differential (39k miles) for $530 and had it installed for $470. Fixed the differential noise problem. Now I'm just dealing with bent rear right wheel and inside edge tire wear.

deltasierra · Post by **deltasierra** » Fri Jun 23, 2023 5:15 am

As it’s had a heavy impact on the rear wheel the suspension may be affected so get 4 wheel tracking done when you have a new wheel and tyre

javis20 · Post by **javis20** » Fri Jun 23, 2023 2:03 pm

Yes, I plan to do that. Lowest price I can find for the wheel is $480 shipped and about $525 for 2 rear tires. Then add mounting, balancing and alignment. Ouch

javis20 · Post by **javis20** » Sun Jun 25, 2023 9:34 pm

Well yesterday I pulled the problem wheel because I wanted to have a closer look at the wheel liner (since I plan to add sound deadening to it). Anyway, with the wheel removed I got the idea to take it to a tire specialty shop to get their opinion. As I rolled the tire in, the guys in the shop said "hey there's something wrong with that tire". "It rolls like it has a damaged cord". When they put it on their balancing machine, the wheel was very distorted. As he spin the wheel the radius was off by about 10mm from low to high point.

Very disappointed with BMW dealer. I had them put brand new tires on the car a little more than 2 years ago. I thought the cars noisy ride would improve, it didn't. Assumed the tires were just noisy. Everyone said the ride would improve when I ditched the run flats. To make a long story short, I believe the dealer installed and did a 4 wheel alignment with a bent wheel. How could they not see the wheel was bent? When I ask them to diagnose the source of the noise, they identified the tires and differential. The differential was only about 15% of the noise. They would have again put tires on a bent wheel.

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