This bulletin applies to BMW M5 sedans built from November 2017 through May 18, 2018.
A clicking noise may be heard from the area of the rear axle differential either when transitioning from forward to reverse or during load reversal while driving. A slight amount of movement can exist between the mating surfaces of the propeller shaft coupler notches and the mating splines on the rear differential.
Reproduce the noise during a brief road test while the drivetrain is at operating temperature. 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 should occur at engine torque of 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.
Disconnect the rear of the driveshaft. Apply sealant (Loctite 648 or equivalent) to the connection between the driveshaft and the rear axle.
Apply evenly all around the inside circumference in a bead shape - start approximately 10mm back from the outer edge. Bead depth needs to be about 10mm and 5mm thick. The driveshaft must be connected to the output flange within 12 minutes.
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 period.
