BMW Coupes and Sedans 1970-1988 Repair Guide

Brake Pads

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INSPECTION



Measure the thickness of the entire pad assembly or the lining itself as specified in the "Brake Specifications Chart" and replace a pad which is at or near the wear limit. In case local inspection law specifies more lining material as a minimum requirement, the local law should take precedence.

REMOVAL & INSTALLATION



Models equipped with anti-lock brakes require expensive and specialized equipment to bleed the brake system. If you do not own or have access to this equipment, it is best to have a properly equipped professional perform this procedure.

Sliding Caliper Equipped Models

See Figures 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10

This type of caliper is most easily identified by the retaining bolts used to secure the caliper to the brake assembly as well as a single bleeder nipple.

  1. Raise the front of the vehicle and support safely with jackstands. Remove the wheel and tire.
  2.  
  3. Remove a sufficient quantity of brake fluid from the master cylinder reservoir to prevent the fluid from overflowing the master cylinder when the piston is pressed into the caliper bore.
  4.  
  5. If equipped, unfasten the electrical connector from the brake pad wear indicator and then pull the wires out of the clamp.
  6.  
  7. Remove the pad retaining pins and any retaining clips holding them.
  8.  
  9. Remove the anti-rattle and spreader springs. note the correct positioning of the springs prior to removal. Replace if necessary.
  10.  
  11. Force the old pads away from the brake disc (rotor) for easy withdrawal. This can be done using a pair of pliers. Lift the pads out of the caliper.
  12.  



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Fig. Fig. 1: Exploded view of sliding caliper assembly



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Fig. Fig. 2: If equipped, unfasten the wear sensor harness



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Fig. Fig. 3: Compress the caliper using a C-clamp-this can be also done after the caliper has been removed



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Fig. Fig. 4: Remove the rubber cap(s) protecting the caliper retaining hardware



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Fig. Fig. 5: Use an Allen key, Torx® driver or hex wrench to remove the retainer, as needed



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Fig. Fig. 6: ... and grease the shaft to prevent caliper sticking



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Fig. Fig. 7: Remove the front brake pads, then inspect the rotor and pads for wear or damage



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Fig. Fig. 8: If the pads are equipped with wear sensors, remove and check each sensor for signs of wear



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Fig. Fig. 9: Before installing the retaining hardware, apply loctite® or equivalent thread lock to the threads ...



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Fig. Fig. 10: When both retaining bolts are loosened, slide the caliper off

To install:
  1. Check the brake disc (rotor) for excessive grooves which would indicate that the rotor(s) would need to be cut or replaced.
  2.  
  3. Examine the dust boot for cracks or damage. Push the piston(s) back into the cylinder bores using a C-clamp or other suitable tool. If the pistons are frozen or if the caliper is leaking hydraulic fluid, it will require overhaul or replacement.
  4.  
  5. Slip the new pads into the caliper and then install one pad retaining pin and clip. Position the anti-rattle springs and/or spreader springs and then install the other pad retaining pin and clip.
  6.  
  7. Refill the master cylinder with the correct brake fluid.
  8.  
  9. Replace the wheel and lower the vehicle. Pump the brake pedal several times to bring the brakes into correct adjustment. Road test the vehicle.
  10.  

If a firm pedal cannot be obtained, the system will require bleeding. Refer to the procedure in this section).

Fixed Caliper Equipped Models

See Figures 11 and 12

A fixed caliper can be identified by multiple bleeder nipples and drive pins securing the brake pad in place. With this type assembly, the caliper does not have to be detached from the rotor to remove the brake pads.

  1. Raise and support the front of the vehicle safely on jackstands. Remove the wheel and tire.
  2.  
  3. Siphon a sufficient quantity of brake fluid from the master cylinder reservoir to prevent the fluid from overflowing the master cylinder while removing the pads. This is necessary as the pistons must be forced into the cylinder bore to provide sufficient clearance to remove the pads.
  4.  
  5. Grasp the caliper from behind and pull it toward you. This will push the piston back into the cylinder bore.
  6.  



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Fig. Fig. 11: Fixed caliper front brake. Notice the drive pins (arrows) and the tension plate (1)



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Fig. Fig. 12: If equipped, remove the pad wear sensor and inspect. Replace if needed

  1. Disconnect the brake pad lining wear indicator, if equipped.
  2.  
  3. Using a suitable punch, drive out one of the drive pins securing the brake pads in place in the caliper. as the pin is driven out, the pad tension plate will drop out.
  4.  
  5. Drive out the remaining brake drive pin.
  6.  
  7. Remove the brake pads by sliding them out the caliper opening.
  8.  

To install:
  1. Check the brake disc (rotor) for excessive grooves which would indicate that the rotor(s) should be cut or replaced.
  2.  
  3. Examine the dust boot for cracks or damage, then push the piston back into the cylinder bore. If the piston is frozen or the caliper is leaking brake fluid, it will require overhaul or replacement.
  4.  
  5. Slip the new pads into the mounting bracket and then install the caliper in the reverse order of removal.
  6.  
  7. Refill the master cylinder with the proper brake fluid.
  8.  
  9. Replace the wheel and lower the vehicle. Pump the brake pedal several times to bring the brakes into correct adjustment. Road test the vehicle.
  10.  

If a firm pedal cannot be obtained, the system will require bleeding. Refer to the procedure in this section).

 
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