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The correct way to adjust handbrake with what I refer to as ‘Type 1′discs is to loosen the cable adjuster off and adjust the handbrake shoes themselves. To do this you first need to remove the brake caliper bracket to be able to remove the brake disc. In our example (VK Commodore) it had two 17mm bolts securing it to the axle housing. The cable adjuster should be easy to find, just follow the handbrake cable along the floor of the car and it should be easily seen. In our example the adjuster has two 13mm bolts locked together requiring two open end spanners. Once the disc is removed you will see two brake shoes, fixed at the top with a knurled adjuster at the bottom.

Sorry for the poor picture, the old girl hasn’t seen the road for a while! The adjuster is just visible between the two brake pads. Turning the knurled nut by levering with a screwdriver will move the shoes in or out. What your aiming to have is the shoes just touching the inside of the disc rotor. Adjust the shoes until you can refit the disc and turning by hand you can hear the shoes rubbing against the disc. You should still be able to turn the disc easily by hand as having the shoes too tight will cause binding once they heat up.

  Once you are satisfied you have both sides adjusted correctly refit the brakes, making sure everything is tight. Refit the wheels and then using the cable adjuster, tighten until the handbrake lever comes up around 6 or 7 clicks (don’t push the button in and listen for clicks). If the cable adjuster has two nuts make sure to lock the two together. Final step is to check that both rear wheels are turning freely without binding. Once this is done time to shred some tyres, I mean time to road test!

Take care and be safe on the roads.

Craig

First of all I will cover the type of rear disc brakes mainly found on Commodores and late model Falcons. They have the handbrake mechanism set up as a drum brake inside the rotor. If you need to adjust the handbrake please read the Handbrake adjusting post. Replacement of the brake pads on this set up is very easy. Once again check the thickness of your rotors to determine if you need to replace them as well.

 Removal of the brake pads is as simple as removing the 15mm bolt  from the bottom caliper slide. You will have to hold the caliper slide from turning with a 17mm open end spanner. Once you have the bolt removed pull the caliper up from the bottom and slide the caliper out of the bracket. Remove the brake pads and push the piston back into the caliper using either method described in the front pad replacement post.

One of the most important aspects of replacing brake pads is ensuring that the new pads have the best chance of a long life. Nothing worse than one side wearing down completely and the other side having plenty of meat left on the pad. One cause of this is sticky or siezed slides in the caliper bracket. If they feel sticky or are stuck in the bracket work them loose and apply some anti-sieze compound or high-temp grease. This will help to maintain even brake pad wear.

Once you have the old pads out and the piston pushed back, fit the new pads and slide the caliper into the top bracket hole. Push the caliper down over the brake pads, making sure both spring clips are in the correct position. Refit the 15mm bolt and tighten using your 17mm open end spanner to hold the slide from turning. Refit the wheel and repeat on the other side. Once you have both sides finished pump the brake pedal until you have a firm pedal, check the brake fluid level in the master cylinder and road test. Use several firm stops from around 60km/hr to bed the brake pads in. If the new pads came with bedding-in instructions follow them, as some manufacturers have different ways of doing this. That’s all there is to it!

Take care and be safe on the roads.

Craig

  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