Brakes: things that slow you down. The motoring equivalent of an anchor.

Brakes come in two forms, disks and drums. All brakes use pads and are operated hydraulically.

Brake Disks: round steel disks that rotate with the wheels, gripped by brake pads when you squeeze the brakes and therefore slowing the car down. You can often see them shining if you look through your wheels. Alarmingly they can look rusty sometimes, but that’s usually only because it’s rained and you haven’t driven the car – normally nothing to worry about. Disks wear out over time and will need replacing, but not as often as brake pads. Although disk brakes are very efficient and can dissipate heat pretty well, after protracted use they can get very hot, which can dramatically reduce their effectiveness. For this reason it’s best to put the car into a lower gear (ie. from fourth to third) when coming down a long hill, so that you can use the engine to slow you down rather than riding the brakes.

Drum Brakes: old-school these days, but still seen sometimes on smaller cars and older cars, but only on the back wheels. These brakes actually look like a drum and the pads press outwards from the inside of the drum, creating friction and slowing the car down. As you’ll remember from school though, friction creates heat and in a drum brake there’s nowhere for the heat to go. This means that drums brakes overheat much more quickly than disk brakes and are prone to “fade” (a technical term for complete failure). Very old cars had drum brakes on the front wheels as well, thus ensuring that the motoring population was kept under control.

Brake Pads: Often seen in your servicing bill, brake pads are relatively soft and grip the brake disks (or push against the inside of a brake drum) when you want to slow down. The harder you push the pedal, the harder they squeeze and the more they wear out. They also generate a lot of heat, so at the risk of repeating ourselves, watch out if you’re going down a long hill constantly riding the brakes – they can catch fire and become so hot they stop working altogether! Don’t do it, change to a lower gear and use the engine to slow up. Brake pads used to be made from asbestos, but thankfully the manufacturers now leave the passengers to kill themselves without any help.