Contents: Removal ↡ Installation ↡
Removal
1. Remove the rear brake disc as described in paragraph 7, recording the correct placement of all parts (see fig. 14.1).
Fig. 14.1. Parking brake parts (left side shown)
1 Brake cylinder
2 Rear hub holder
3 Parking brake shoes
4 Regulator pin
5 Knurled adjustment ring
6 Regulator body
7 Fastening spring
8 Cable mounting bolt
9 Cable tip
11 Mounting bolts
12 Upper return spring
13 Lower return spring
2. Using pliers, compress the shoe mounting springs, then turn them 90° and remove them from the lower brake plate. Access to the springs is through the holes in the hub flange (see fig. 14.2).
Fig. 14.2. Remove the mounting springs...
3. Carefully unhook and remove the lower return spring of the parking brake shoe, remembering how it is installed - it is not symmetrical (see fig. 14.3).
Fig. 14.3. ...then unhook the lower return spring, paying attention to which cut it is installed...
4. Separate the lower ends of the pads from the expansion mechanism and remove the unit from the vehicle (see fig. 14.4).
Fig. 14.4. ...and remove the parking brake shoe assembly from the vehicle
5. With the assembly on the workbench, make sure each part is in the correct position, then unhook the upper return spring and separate the shoe adjustment mechanism.
6. Inspect the pads. If they are worn or dirty, replace them. It is also recommended to replace the tension springs. Mercedes-Benz does not set a wear limit for the parking brake pads, but pads with a friction material thickness of about 1.5 mm should be replaced.
7. If the pads are to be changed, clean and check the condition of the pad adjuster and expansion mechanisms. If wear or damage is detected, replace them. If everything is normal, apply a fresh layer of brake paste to the adjuster threads and the sliding surfaces of the expansion mechanism (mercedes-Benz recommends Molykote Paste U or G-Rapid). Do not allow the paste to come into contact with the friction material of the pads.
Installation
8. Before installation, clean the base and apply a thin layer of high-temperature brake paste (see item 7) or "anti-seize" compound to all surfaces of the base that come into contact with the brake pads. Avoid getting the paste on the friction linings.
9. Assemble the shoes and adjuster mechanism, taking into account that the adjuster must be installed with the knurled adjuster ring at the front. Pull the adjuster out completely and install the upper return spring.
[Information copied from the website: MERCEDESMAN]
10. Install the assembly into place and align the lower ends of each shoe with the expansion mechanism.
11. Install the lower tension spring so that the longer hook is attached to the upper shoe (see fig. 14.11).
Fig. 14.11. Longer hook of the lower return spring (shown by arrow) must be installed on the upper parking brake shoe
12. Make sure the pads are positioned correctly and secure them with the retaining springs.
13. Check that all parts are installed correctly and center the parking brake shoes.
14. Install the brake disc as described in paragraph 17. Before installing the wheel, adjust the parking brake as described in paragraph 13.