Whenever I drive slowly around 20 mph over uneven roads and bumps, I hear this knocking sound from the rear of the car. It also happens when I swerve back and forth or rock the car by pushing as in the video. Nothing seems loose in the boot, spare tire, muffler areas, or hatch.



When I brought the car to the dealer, they diagnosed a different sound from the front due to a loose transmission bolt. Ironically, I had complained about this sound last year, and they couldn't find anything before. I plan to bring the car in again to drive it with the foreman.

I'm thinking it's the rear sway bar bushing as posted by Helix13mini in another thread:

SI M33 02 09
Rear Axle January 2010
Technical Service

Load Graphics
SUBJECT
Rattling and/or Knocking Noise from the Rear Axle


MODEL
R55, R56, R57 without Sport Suspension


SITUATION
A rattling and/or knocking noise may be heard from the rear axle and/or rear
suspension while driving over uneven roads.

CAUSE
The inner diameter of the stabilizer bar mounts may be too large for this
application.

PROCEDURE
[GRUSB3309-02.JPG]
Use a caliper gauge to determine whether the rear stabilizer bar is 16mm
(1) (non-sports suspension). If the stabilizer bar is 16mm, replace the
stabilizer mounts (2) with P/N 33 55 6 754 823.

PARTS INFORMATION
Part Number
Description
Quantity

33 55 6 754 823
Stabilizer mount
2





WARRANTY INFORMATION
Covered under the terms of the MINI New Vehicle Limited Warranty

Defect Code:
33 55 01 39 00


Labor Operation:
Labor Allowance:
Description:

33 55 021*
Refer to KSD2
Replacing both rubber mounts for stabilizer