Front

NOTE:
- If the wear of the brake pads is excessively high or one-sided, check the pistons for easy motion. If the pistons are hard to move then you should recondition the caliper.
- Pads should be replaced when they are down to 2 mm or if they are greasy/oily. Use pads approved by Mercedes-Benz.
- If the pads are worn beyond permissible wear limits down to the back plate, damage may result to the fixed caliper because the web between the sealing ring and the dust cap can break out resulting in a leak. In this case, carry out a high and low pressure test.
- Brake discs with severe lining deposits on the braking surfaces (visible by grey or blue discoloration) must be cleaned using Mercedes special disc cleaning pads before installing new pads.
- Due to the limited clearance between the brake caliper and wheel rim on models 124.031/034/051/091 it is necessary to install a spring lining clip with retaining lugs for the contact sensor. Pay close attention to cable routing before disassembly.





1. On fixed calipers with brake pad wear indicators, pull cable for contact sensor (S/10/1) out of plug connector (52) on fixed caliper. Pay attention to spring lining clip in models 124.031/034/051/091.




2. Knock out retaining pins with punch (35) and remove spring lining clip. When reinstalling, position spring lining clip, then drive in retaining pins, with aid of punch, up to the stop.







3. Push pads back slightly and remove brake pads using special removal lever tool (34) 123 589 13 33 00 or equivalent and pull contact sensor out of the backing plate of inside pad (43).




4. Clean brake pad guide with special brake caliper brush tool No. 000 589 26 68 00, or equivalent.




5. Evacuate some brake fluid from reservoir to prevent overflowing and force back piston with resetting special tool (31) 000 589 52 43 00, or equivalent.

NOTE: On four piston Calipers, press one opposing pair with the resetting tool and to prevent the other pistons from falling out use plastic wedges 601 589 05 19 00.

6. Check dust caps for damage. If damaged, remove caliper and recondition.




7. Check rotors for wear and observe dimensions using Vernier gauge 124 589 00 15 00 and replace rotors if needed.




8. Coat side contact surfaces lightly, without circumferential damping, of brake pad lining backplate with brake pad paste 0019891051 before installation.




43 Brake Pad
a Circumferential Damping
b Grease Packing
c Stainless Steel Plate

Install brake pads with circumferential damping dry.

9. After installing pads actuate brake pedal several times. Then check and correct brake fluid level in reservoir.
10. Carefully break in new brake pads by braking the vehicle several times from 80 km/h to 40 km/h using only slight pedal pressure and allowing sufficient time for brakes to cool slightly between each deceleration. Brake at high deceleration rates only after pads have been properly broken in.

Special Tools: