Some 2010 Ford Transit Connect vehicles may exhibit a thumping or knocking noise from the rear when braking. The cause may be the set screw effect of the rear drum inner friction surface during initial braking, when rear shoes first touch the drum.
When new shoes initially touch the drum inner surface, there may be a tendency for the shoes to follow the turning marks (directional grooves in the surface finish), move laterally and hit the backing plate in each wheel rotation. This can cause a repeating knock-knock noise. The noise will continues until bedding occurs between the shoes and drums.
1. Apply the parking brake three notches.
2. Drive the vehicle at a maximum speed of 15 mph in first gear for 820 feet.
3. Drive the vehicle 820 feet in reverse.
4. Release the parking brake and wait at least 15 minutes.
5. Road test to verify that the noise is gone.
6. If the noise remains, install each drum to the opposite side (swapping the drums changes the direction of the grooves).
7. Adjust the parking cable per the service manual, section 206-05.