Brakes are pretty much the most important safety device on your car. If you’ve ever partially lost your brakes in the past, you’ll agree that it’s not something you want to experience again. Inspecting your brakes twice a year for wear and damage can protect you and your passengers. Additionally, it will also help save you money by catching any damage before it becomes too costly.
Brake System Components That Can Fail
The master cylinder, the heart of the vehicle’s braking system, holds the brake fluid when it is not being delivered to the brakes through the brake lines. If brake fluid leaks because the master cylinder is worn or brake lines are plugged or broken, the fluid cannot be delivered, and the brake pads will become ruined.
The brake fluid itself can become dirty or contaminated as it draws rust-causing moisture and picks up other debris, or it can break down from excess heat. Clean brake fluid is either clear or slightly yellow, while dirty brake fluid may be brown or even black. Old and dirty brake fluid can damage ABS brake systems internally.
The brake lines connect to the master cylinder through a combination valve, which combines a metering and proportioning valve. It regulates the pressure on the front and rear wheels to make sure both sets of brakes are applied simultaneously. A malfunctioning combination valve may cause the wheels to lock up.
Brake pads and shoes can be made of ceramic, metal or organic materials, while the disc rotors and drums they press against are made of metal. Because the pads and shoes create friction to stop the car, they gradually wear down over time and may wear away completely, letting the metal of the calipers and cylinders they are attached to grind against the rotors and drums and damage them. Some pads have a metal strip attached that sounds a warning whistle when the pad becomes too worn, but this strip sounds only when the car is in motion and the brakes are not applied.
How to tell a complete brake job from one that’s not
Ever wonder how repair shops know what cost to advertise for a brake job if they don’t know what the problem is? They don’t. We believe you can only tell what a brake job will cost after a thorough inspection of the brake system. You really do get what you pay for.
How Brakes Work
When you press down on the brake pedal, brake fluid is sent from the masters cylinder, which is the little white box under the hood of your vehicle, through brake fluid hoses down to the brake calipers.
With hydraulics, the brake fluid causes the caliper, which houses two brake pads, to squeeze against the spinning rotor in each wheel. This action creates friction and slows the vehicle. Some vehicles have drum brakes in the hack. When the brake pedal is pushed, a piston pushes the brakes shoes against the drum.
Through use, the friction material on the brake pads and the surface of the rotor wear down and get dirty and rusty. Parts need to be cleaned, replaced and readjusted.
There is a difference in brake repair
THERE ARE COMPLETE JOBS & JOBS THAT AREN’T.
- TEST DRIVEN- Your vehicle is taken for a test ride to verify your problem.
With a minimal brake job most don’t bother with a test drive.
- COMPLETE M.A.P. INSPECTION IS DONE- The brakes of all four wheels are checked, including the parking brakes using the Motorist Assurance Program guidelines. The results are documented and explained to the customer.
A lot of garages don’t follow M.A.P. guidelines.
- A QUOTE IS GIVEN- A quote is given on what is needed, and only an approved repair is done, which includes servicing the rear brakes. They are cleaned, re-lubricated and adjusted.
Most only check the front brakes because they wear faster than the rear.
- FLUID IS CHANGED- Old, dirty brake fluid in the master cylinder is drained and replaced.
Other garages don’t replace the contaminated brake fluid.
- .ROTORS ARE MEASURED AND CHECKED- Thickness variation of all the rotors is measured with a micrometer. Variations can cause brake pedal pulsation or the steering wheel to shake as the vehicle stops. The rotor vanes, or cooling fins, are checked for mud and rust. Clogged vanes could affect the rotors’ ability to remove heat from the brakes. This could lead to premature wear.
Not every garage does this.
- FLUID IS REPLACED FROM THE LOWER PART OF THE SYSTEM- The dirty brake fluid is drained. A special clamp is attached to the hose leading into the caliper before pushing in the caliper piston to remove the caliper. This prevents the remaining contaminated fluid in the caliper from flowing hack into your vehicle’s anti-lock braking system, which can easily damage that costly unit.
Many force the piston in and push dirty fluid hack into the ABS unit.
- WHEEL HUB IS CLEANED- Dirt and rust build-up is cleaned from the hub and the hardware is replaced. Not cleaning the hub can cause lateral run out. (See step 8.)
Others don’t take the time.
- EACH HUB AND ROTOR ARE CHECKED FOR LATERAL RUN OUT- A new or resurfaced rotor is checked for lateral run out when its attached to the hub. That’s when the rotor, while spinning, is not perpendicular to the wheel and it wobbles. It causes extra rotor wear and pedal pulsation
- PARTS ARE LUBRICATED- All metal-to-metal parts are lubricated.
Others don’t take the time.
- PROPER TORQUE IS USED- The wheels are put back on, each torqued to the proper specifications.
Many don’t torque at all.
- CALIPERS ARE READJUSTED- Break pedal is gently pumped to get the calipers readjusted.
Pumping too fast can damage the master cylinder.