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Issue with back noise on 330D M-Sport Touring NEED YOUR HELP

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andy_bmw_1965
Posts: 60
Joined: Mon Feb 02, 2026 8:37 pm

My 1991 BMW 330D Touring is malfunctioning.

From behind the vehicle, there is a deafening screech that sounds like a Chinook helicopter. At speeds of sixty miles per hour or above, the sound becomes audible.


The noise also comes in when I apply power when on a left-hand turn.

A mechanic has already looked at the vehicle. I had the wheel bearing on the front passenger side replaced since they thought it might be a wheel bearing. In addition to having the differential and rear bearings serviced, I had the failed rear shocks replaced.

Feb 2025 was the date of the differential replacement.

Even so, you can still hear the sound.
andy_bmw_1965
Posts: 60
Joined: Mon Feb 02, 2026 8:37 pm

I get that the traffic noise can make it difficult to hear.

I would really value any assistance.
LiamTheGreat
Posts: 79
Joined: Mon Feb 02, 2026 8:35 pm

Perhaps wheels need to be adjusted? Anything more besides shocks that goes into the suspension?
andy_bmw_1965
Posts: 60
Joined: Mon Feb 02, 2026 8:37 pm

The noise was present both before and following the time I had the wheel alignment taken care of, which was when I got two new tires for the back.
GURU4U2BUY
Posts: 38
Joined: Mon Feb 02, 2026 8:40 pm

A polyurethane connector, a center bearing, or a universal joint on the shaft of the propeller.
It could be a front tyre that has delamination.


You replaced the diff for what reason?
andy_bmw_1965
Posts: 60
Joined: Mon Feb 02, 2026 8:37 pm

There was a deafening screech as the bearings failed.
tonysoprano
Posts: 40
Joined: Mon Feb 02, 2026 8:43 pm

100% sensor and wheel bearing at the same time; I believe I came up with the term "chinook" when this first occurred to me (around 2013 or 2014). Make a drive, spray water on both discs, but you'll quickly tell which one it is.
andy_bmw_1965
Posts: 60
Joined: Mon Feb 02, 2026 8:37 pm

With the goal to detect any accumulation of heat, I invested in a temperature gun.
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