The Brakes in Your Car
Introduction
The design requirements for increasingly efficient and safer cars have had a marked effect on design and performance of the brake system in your car. Gone are the days when a set of discs lasted virtually the lifetime of the vehicle, and when a set of pads could be changed at home on a Saturday afternoon.
Now we have to deal with several designs of hi-tech traction control, brake discs that are themselves consumable parts, brake systems that are controlled by the central processing system, and vehicles that have become so light that any out-of-tolerance revolving component can threaten to shake the suspension apart.
In short, caring for brakes has become a specialist industry that has had to invest heavily in technology. Even the SABS-specified testing equipment at our roadworthy centres is outdated by European norms - they can measure the balance of the braking effort between left and right wheel, but they cannot indicate how quickly your vehicle can decelerate. Also, they can not deal with vehicles that have permanent four-wheel drive systems, since they can only test one axle at a time.
The weak links in your brake system
Wearing parts:
- Brake discs and brake pads.
- Brake drums and brake shoes.
- Brake seals in the hydraulic system.
- Sliding bushes and pins in the brake callipers.
Parts that are prone to corrosion:
- The pistons in brake callipers and wheel cylinders.
- The bores of all brake cylinders and valves.
Brake fluid, which can absorb moisture
- The system should be flushed every 12 months.
Important maintenance
- Check the life left in the friction material of your brake pads and brake shoes - the wheels need to be removed to do this. The average modern light vehicle will require new brake pads somewhere between 40,000km and 70,000km if driven carefully.
- Check the moisture content of the brake fluid, and change it regularly as specified in the owner's manual of your car.
- Ensure that the metal friction surfaces are not grooved or uneven when new brake pads and brake shoes are fitted - it should be machined or replaced if required.
- Have experts perform a dynamic brake test on your vehicle to ensure that the vehicle will stop in a straight line under emergencies, and that the proportional valve operates satisfactorily.
Do not expect franchise dealers to have the specialized equipment or training required to check brake components and brake fluid.