Braking Systems - Discs/Pads & Drums/Shoes

June 30, 2017
Braking Systems - Discs/Pads & Drums/Shoes

INTRODUCTION TO BRAKING

The brakes are one of the most important safety devices on your car so it is important that they are working correctly, they are also a significant part of the MOT testing procedures too and are a common cause for MOT fails. There are two common braking systems in use in the Uk, these are discs/pads and drums/shoes, some vehicles will use all of one system and some will use a combination of the two. For the majority of cars on the road, discs/pads are on the front and then disc/pads or drums/shoes on the rear.

DISCS & PADS

In the simpliest form, this setup is where you have a disc attached to the hub on the wheel and sitting on either side of the disc is a brake pad, when you apply the brakes hydrolic fluid pumps to the caliper which acts as a clamp and presses the brake pads onto the disc. The brake pads have a thick friction based material on them which causes fraction and thus slows the car down. Over time the friction material on the pad wears down and the braking becomes less effecient, eventually you will hear sqeaking and squeeling noises from your brakes and this is the time to change them asap, if you don’t eventually you will be braking metal onto metal and will experience a deep grinding noise. If you replace your brakes as soon as they have worn down you will get the most life from your discs, if you fail to do this you run the risk of warping or grooving the discs and they would also require replacement. Your pads will always be checked as part of our multicheck servicing procedure.
Common ailments
  • Sticking / Seized caliper
  • Brake pads wearing low
  • Brake pads worn incorrectly or producing noise
  • Pitted, grooved or warped discs
  • Worn, damaged or leaking brake lines

DRUMS & SHOES

This is the older braking system but is still comonly used on the rear cars, some older cars (classics etc) are likely to have drum brakes all around. A drum brake consists of a set of brake shoes that sit inside a drum with a wheel cylinder, when applying the brakes the wheel cyclinder pushes the shoes outwards onto the inside rim of the drum causing it to slow down. The shoes, just like brake pads are coated with a friction material which when pushing outwards against the drum causing the wheels to slow down. Again the shoes friction material will wear down and cause noises or grinding when completly worn and will require replacement before it gets to this stage to avoid damage.
Common ailments
  • Shoes have worn low
  • Shoes are missing clips or springs
  • Wheel cylinder is seized
  • Wheel cylinder leaking
  • Rusty, grooved, worn brake drum

OTHER COMPONENTS

There are many other components which can be part of the braking system which are prone to go wrong and should never be ignored if any symptons occur that you wouldn’t see in normal operation.
  • Master Cylinder
  • Brake Lines
  • Brake Pedal / Pedal Switch
  • ABS Controller / Pump
  • ABS Dash Light
  • Handbrake Cables
If you feel like you have an issue with your brakes, or just want us to check them over then please give us a call on 01424 870 307 or use our contact page to send us a message.