Parts of a car's braking system are designed to wear down and as this happens, they will lose their effectiveness. How often should a car's braking system be inspected? It is recommended that you have the major components of the brake system be inspected once a year or about every 10,000 miles. How often you have the brake system inspected depends on things such as how you drive (how you stop in particular), the age of your car, the type of braking system, whether you live on hilly versus flat lands, highway versus city driving, and the type of braking system that you have. Inspecting under the hood Check the level of brake fluid in the master brake cylinder reservoir. Top it off if neccessary. Be sure not to let any kind of dust or dirt enter the reservoir. If you need to add more than 2oz of brake fluid frequently, there may be a leak somewhere in the brake system. The brake fluid should be clear, not dark in any way. If it is, it may be time to have it replaced. Inspecting the Brake System while driving If the brake pedal goes almost to the floor or looses its firmness, there may be a leak somewhere in the braking system or the brake fluid level in the master brake cylinder reservoir has gotten low. A vibrating of pulsating feeling in the brake pedal and/or the steering wheel may be a sign that the brake pads and rotors or brake shoes and drums need to be resurfaced or replaced. A light squealing sound is normal, especially when the car is cold. If you hear a metal to metal sound, have your brakes inspected immediately. Underneath the Car Inspect the metal brake lines that run the length of the car and also the rubber hoses that deliver the brake fluid to the brake calipers and make sure that the lines and hoses are not damaged in any way and also that they are free of any moving or heat producing parts. Inspecting Disc Brakes On disc brake systems, the parts that are designed to wear down are:
" brake pads
" rotors, also called discs
" calipers, in particular the piston or pistons inside of them

Inspect the condition of the brake pads and rotors and also check to make sure that the piston inside of the caliper is working properly. Inspect the overall thickness of the brake pads and rotors. Brake pads that show excessesive wear should be replaced. Rotors that have slight wear should be resurfaced or replaced and rotors that show excessesive wear should be replaced. Brake pads and rotors with light scratches can mean that there is a contaminent such as dirt lodged between them. At the very least clean them or have them cleaned with a brake cleaner. Rotors with deep scratches should be replaced with new ones or resurfaced. Inspection of Drum Brakes On drum brake systems, the parts that are designed to wear down are:
" brake shoes
" drums
" wheel cylinders

Remove the drum so that the inside can be inspected. Inspect the inside of the drum for any damage that is done to it. Any brake dust buildup should be removed with a brake cleaner. If there are heavy scratches to the inside of the drum, replace both drums. A wheel cylinder that is defective will leak brake fluid from its sides (where the metal meets the rubber part). warning: when working on the car's braking system, do not inhale any brake dust. It is recommended that you wear a face mask when working on the brakes themselves.