Back To Basics: Brake discs and pads

Rob Hawkins investigates routine servicing of brake discs, showing how to remove, inspect and clean brake pads and outlining the common problems that can arise with them.

Routine servicing of a vehicle’s brakes used to involve a complete stripdown, including the removal and cleaning of the brake pads, but many service schedules for modern cars only stipulate a visual inspection, perhaps to save time and labour charges. However, very little has changed with brakes to warrant only a visual inspection, and a routine stripdown and clean-up helps to prolong their life. So, the following pages provide a general guide to servicing brake discs in this manner.

There are numerous safety points to note when servicing brakes. The vehicle will need to be raised and secured with at least one axle stand to be able to remove a road wheel, so make sure it is on level ground with at least one wheel chocked. Spray over the brakes with a dedicated brake cleaner (bought from accessory stores) before working on them to help dampen any brake dust; and if you have respiratory problems, wear a breathing mask to reduce the risk of inhaling it. Similarly, wear gloves to protect your hands.

If your vehicle has an electronic park brake (handbrake), it must be switched to service mode to avoid the risk of the handbrake being activated and causing injury. Do not work on these brakes unless this has been done.

If a new set of brake pads needs to be fitted, new pads must be fitted across an axle (eg, all pads on the front brakes).

The pistons inside the calipers will probably need to be retracted to make room for the new pads. And new pads usually need to be bedded-in, which means harsh braking should be avoided for at least the first 100 miles of driving.

Always check the brake fluid level in the brake fluid reservoir (normally located in the engine bay) before and after working on the brakes, and pump the brake pedal to check it’s firm before driving.

There are numerous precautions and different practices when working on brakes. For instance, some should be dry-fitted whereas others benefit from a little brake grease and should be kept well away from copper grease. The following pages help to explain more.