This article will show you how to replace the Brake Discs (Rotors) and Brake Pads on an MX5 and other types of car with similar braking systems.
For the purposes of this article we will be changing the front Brake Pads and Discs on a 1999 NB Uk Spec MX5. Rear brakes are similar with the notable exception of the need to also remove the upper caliper bolt in order to remove the brake caliper and gain access the brake pads. On earlier and later models, and with other makes of car, the brake components may differ in appearance, in which case use this article as a general guide only, and adapt the instruction where required.
Brake Disc and Pad Replacement is the perfect MX5 DIY project to carry out at home, requiring only a handful of tools, the replacement parts, and the jack from your boot. Brake Pads and Brake Discs should always be replaced in axle pairs. Given the limited cost of new Discs, usually around £20 each, I tend to replace both Pads and Rotors at the same time. If you are only replacing the brake pads you can skip the section related to the brake disc removal and replacement.
Removing Brake Caliper and Pads
Loosen each wheel nut half a turn, before jacking up the car. Once the car is jacked up, remove the wheel nuts and remove the wheel.
Remove the lower caliper bolt as shown in the picture below. On the rear brakes (or other cars) you may need to also remove the upper bolt.
The caliper can now be rotated upwards and then slid towards you to remove it from the upper pin. Using a piece of wire or a bungee cord, hang the brake caliper from the suspension to keep it out of the way. Do not let the caliper hang by its brake hose.
Remove the upper and lower springs from the brake pads, then withdraw the pads from the caliper, noting orientation if they are to be refitted. Remove and clean the shims from the top and bottom of the caliper bracket.
Removing Brake Disc (Rotor)
If you are replacing the Brake Disc Rotors it will be necessary to remove the caliper bracket. Undo the top and bottom retaining bolts and withdraw the bracket from the hub assemble.
There may, or may not be, a small screw between one of the wheel studs, attaching the Brake Disc to the Wheel Hub. Don't worry if you do not have a screw, or the screw is missing, it simply helps keep the disc in place, it is ultimately held in place by the wheel studs.
If the disc will not come free with a sharp tug, strike the area in-between the wheel studs with a hammer several times, or tap the rear of the disc to help it break free.
Fitting New Brake Discs (Rotors)
Before fitting your new brake disc it is important to clean off the anti-corrosive grease applied to the rotors to prevent rust during storage. Clean the mating surfaces with brake cleaner to remove any residue and to prevent contaminating your brake pads!
Once clean, the new brake disc can be placed onto the hub, and secured with the fixing screw (if present). Refit the brake caliper bracket to the wheel hub assembly using the two bolts. Apply a little copper grease to the threads to prevent seizing in future.
Fitting New Brake Pads
Replace the shims into the top and bottom of the caliper bracket. Insert the rear, and then front brake pads into the brake caliper bracket, after adding a small amount of copper grease to the ends of the mounting lugs, where they would make contact with the shim, ensuring not to contaminate the brake pad surface.Reattach the upper and lower springs to the brake pads. Using a pair of large jaw pliers, or a brake caliper compression tool, push the brake caliper piston back into the caliper body, to aid in refitting.
If you removed both caliper bolts, place the caliper back into position over the brake pads, otherwise slide the caliper back onto the top guide pin and then lower the caliper over the brake pads. Secure the bottom of the brake caliper in place with the bottom bolt, after adding a touch of copper grease to the thread and pin.
Finishing Up
Before driving (or moving onto the next wheel) fully depress the brake pedal a couple of times to resettle the brake components back into place. Refit the road wheel and lower the car to the floor, remembering to tighten the wheel studs correctly.After fitting new brake discs or pads a period of bedding in is required before full braking efficiency will be achieved. For the first 100 miles, try to;
- Brake gently and avoid high speed braking,
- Try not to come to a complete standstill after hard braking,
- Keep a safe driving distance until braking efficiency restored.
Did you find this article on replacing brake pads and discs helpful? Do you have a tip or trick to share? Let us know in the comments below.