Easy to do, extremely important to get right! But don’t let that phase you, replacing disc brake pads is and easy job and as long as you are careful all will be good. The vehicle we are doing the brake job on is a 1985 VK Commodore. These brakes are typical of many makes and models over several years and the principles remain the same to all vehicles. Although the mounting bolts or piston layout may be different this guide will be useful for all vehicles. If you are noticing a vibration in the steering wheel or brake pedal when applying the brakes, particuarly at speeds around 80km/hr then the front discs will need machining. Refer to the brake machining post for info.

Parts/Tools required.

1. Replacement brake pads.
2. Spanners/Sockets for removing caliper bolts.
3. Tool for pushing piston back. A pry bar or large screwdriver or large multi-grips can be used however there is a specific tool available at auto shops for doing this.
4. Grease or anti-sieze compound to lubricate the caliper slides.

Doing the job.

1. Raise the vehicle and remove the wheel. Support the vehicle with chassis stands or at the very least position the wheel under the car.
2. Remove the bottom caliper retaining bolt. It may be necessary on some vehicles to remove both top and bottom bolts. In this case we have a 15mm bolt and a 17mm head on the caliper slide so two spanners have to be used.
3. Lift the caliper up and slide it across to release it from it’s bracket. If you had to remove both bolts you may have to pull the caliper towards you to remove it.
4. Remove the brake pads taking note of the position of any spring clips or anit-rattle clips.
5. Squarely push the piston back into the caliper. If you are using a pry bar or large multi-grips be sure to push evenly on both sides of the piston.
6. Fit the new brake pads ensuring that any spring clips or rattle clips are position correctly.
7. Lubricate the caliper slides with grease or anti-sieze compound. Slides that are stuck are a major cause of uneven brake pad wear.
8. Refit the caliper and once you are sure that everything is fitted correctly, refit the retaining bolt and tighten.
9. Repeat on the other side.
10. Check the brake fluid level and then pump the brake pedal several times to push the piston out to contact the brake pads. If you find that the pedal is soft or spongy a bleed of the brake system will be needed.
11. Re-check the fluid level.
12. Refit the wheels and lower the car. Re-check wheel nuts once the car is on the ground.
13. Most brake pad manufacturers will have a list of instructions on how to bed the new brake pads in. Generally this is a series of stops from around 60km/hr to heat the pads, but be careful not to overheat and then ‘glaze’ the pads.

All done! Next week we will take a look at replacing rear disc brake pads. Because the handbrake is usually incorprated in the rear brakes things can get a little tricky. I will try to get as many pictures as I can to illustrate the differences between a few makes and models.

Until then take care and be safe on the roads.

Craig