If this is the reason for the thud here is the BMW Sevice Repair bulletin SIB 26 01 18 search on line for it and it shows a video and has pictures

DRIVELINE CLICKING/KNOCKING NOISE ON LOAD REVERSAL

This Service Information bulletin replaces SI B26 01 18 dated August 2018

What’s New:

• More models added

Model
F90 (M5 Sedan)
F80 (M3)
F82, F83 (M4)
F87 (M2)
Situation

A clicking noise is noticed from the area of the rear axle differential, either when:
Transitioning from driving forward to backing up

During load reversal while driving (i.e., engine load to overrun, etc.)
Refer to video attached to this bulletin.

Cause

A slight amount of movement can exist between the mating surfaces of the propeller shaft (aka driveshaft) coupler
notches and the matching splines on the rear differential.

Correction

Apply sealant to the driveshaft/rear differential connection. The sealant will harden and prevent the relative movement
between splines of the two components.
Procedure
Reproduce the noise during a brief road test while the drivetrain is at operating temperature.

Hint:

Select the Sport display in the Central Information Display using the path My Vehicle- Technology in Action- Sport
Displays. If needed, set the units to pound-feet (lb-ft) using the path My Vehicle- iDrive settings- Units- Torque.
The noise occurs at an engine torque between 37 and 73 lb-ft.

With the vehicle stationary, select transmission gear “R” and accelerate slightly with the brake pedal depressed. The noise should now occur once.
Then select “D” and accelerate slightly against the brake. The noise should now occur again.

Apply Loctite 648 sealant (or equivalent) to the connection between the driveshaft and the rear axle. Refer
Repair Instruction 26 11 000 “Completely Removing and Installing the Propeller Shaft”.
Note:
The updated repair instruction is available with ISTA 4.12.3x, as of late July 2018

The driveshaft does not need to be removed from the vehicle, only the rear joint

Apply Loctite 648 (BMW part number 07 58 9067 732) evenly all around the inside
circumference in a bead shape.
Start approx. 10 mm back from the outer edge (1)
The bead depth (2) needs to be approx. 10 mm, and
5mm thick
Note:
The driveshaft (3) must be connected to the
output flange within 12 minutes.
Copyright ©2022 BMW of North America, Inc.


After installing the driveshaft and tightening the recessed nut, allow a minimum sealant hardening time of three hours

Do not move the vehicle during this time period!

Parts Information

Part Number Description Quantity
33 12 7 607 158 Repair nut 1
26 11 7 527 475 Hex bolt 3
26 12 7 536 563 Self-locking nut 3
07 11 9 906 089 Collar nut 2

Bulk Material

Part Number Description Quantity
07 58 9 067 732 Loctite 648 As needed


Warranty Information

Covered under the terms of the BMW New Vehicle Limited Warranty for Passenger Cars and Light Trucks.

Defect Code: 3310013900

Labor Operation: Labor Allowance: Description:
26 11 000 Refer to KSD2/AIR Removing and installing complete propeller shaft
(Man work)
Or:
26 11 507 Refer to KSD2/AIR Removing and installing complete propeller shaft
(Plus work)
And:
26 99 000 1 FRU Work time to apply a bead of Loctite 648 evenly
around the inside spline circumference as
described in this bulletin.

If you are using a Main labor code for another repair, use the Plus code labor operation 26 11 507 instead of 26 11 000.

Refer to KSD2/AIR for the corresponding flat rate unit (FRU) allowances.

Work time labor operation code 26 99 000 is not considered a Main labor operation. Also, since the “work time” FRU
allowance to be claimed is specified, a separate punch time is not required. However, it still requires an explanation on
the repair order and in the claim comments section.

And:

Sublet – Bulk Materials

Sublet Code 4 See the sublet
reimbursement
calculations below
Reimbursement for the repair-related bulk material
(Do not use part number for claim submission)

Sublet reimbursement calculation for claiming the applicable repair-related bulk material (BMW part numbers) is at the dea
net price for the “quantity used” plus your center’s handling.

Enter this material cost in sublet and itemize the amount on the repair order and in claim comment section.


22 Plus Four KIMI
12 Plus 4 Sport OZZY
08 Roadster FELIX
06 4/4 70th LOKI
77 4/4 SEAMUS
85 4/4 MOLLY