At the same time we attempt to give a reasonable up front price that doesn't double or more once we get it apart. Basic brakes at our shop start at $80 per axle and includes many features which are charged as extras at other shops. If you see a price cheaper than this, WATCH OUT!!! They're going to make money off you some way or the other.
See THE CASE OF THE $19.95 BRAKE JOB!
How Hydraulic Brakes Work
All modern auto and light truck brakes are hydraulic. (except for the parking brake, also big trucks and construction equipment have air brakes)
This means your brake pedal presses a piston inside a cylinder. This applys pressure on the hydraulic fluid in the cylinder. (brake fluid) .
This cylinder which is on the end of the brake pedal is called the "master cylinder".
The pressurized hydraulic fluid from the master cylinder (fluid doesn't compress, so it's almost like a solid linkage) is carried equally to all wheels, which have "slave cylinders."
There are 2 basic kinds of common brakes: disc brakes and drum brakes.
Drum brakes are older, and use two half moon shaped "brake shoes" which are pressed outwards agaist the inside of the "brake drum" by the "slave cylinders", which are called "wheel cylinders". These brakes are found on the rear of most vehicles, and on the front of some new and most older vehicles. (pre 1980)
Disc brakes have a "caliper" for the "slave cylinder", and the caliper presses disc brake pads against both sides of the flat brake rotor. The rotors or drums are attached to the wheels, and the wheels then stop the car.
In 1966 all domestic passenger cars went to a dual master cylinder design: one section operated the front brakes, the other the rear brakes. A proportioning valve was added to limit the brake force going to the rear wheels and make them less prone to "lock up".
Some cars have one front brake and one rear brake operating off the 2 sections of the dual master cylinder. The proportioning valves on these vehicles are a bit more complex than the other type. Even with antilock brakes vehicles still have dual master cylinders and proportioning valves.
Here are some images of
drum brakes and disc brake system components
Power brakes use a booster (either vacuum or hydraulic: hydro-boost units use hydraulic pressure from the power steering pump to assist the master cylinder. The actual brake system still uses brake fluid, not power steering fluid!!) This booster assists you in applying the brakes. As you first press the pedal, a valve opens and operates the booster.
WARNING!!!!!!If your engine dies and you lose power brake assist, THIS DOES NOT MEAN YOU HAVE LOST ALL YOUR BRAKES!!! YOU WILL JUST HAVE TO PRESS THE PEDAL HARDER!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
I've been a mechanic for 22 years now, and I've heard this sad tale at least twice:
Little old lady gets in horrible car wreck. Her story is: "Well, I was coming off the interstate exit in my Cadillac, and the motor died. As you know, this means I lost all steering and brakes!"
I didn't have the heart to inform her that she was mistaken, especially since she swore she would never drive again. She was used to just barely touching the brakes and the car would stop. When she touched the pedal with the usual light touch and nothing happened, she assumed there were no brakes, and went crashing into traffic.
She had to weight 130 pounds: if she'd used the strength of both legs on that brake pedal to apply the brakes, the brakes would have worked and the car would have stopped.
Anti-lock Brake Systems or ABS
Car makers developed antilock brakes many years ago, but recently with the advent of cheap computer stuff (along with the "encouragement" of U.S. auto Safety Regulators) they've started putting ABS brakes on just about every vehicle. Unless your car is over 10 years old it probably has some type of ABS system
The ABS computer senses the speed of the wheels through sensors at each wheel. When a wheel slows down a lot slower than all the other wheels, the computer releases the brakes on that wheel. Almost immediately the computer re-applies the brakes. The computer is, in effect, "pumping the brakes" for you, but doing it much faster than you could.
When the ABS operates the rapid applying and releasing, or "pumping" of the brakes by the computer makes a rather loud noise and vibration. The first time I worked on a car with ABS I thought I'd check it out. When the ABS "kicked in" during my "test" I thought I had broken something on the car!
When ABS was first introduced a trend was noticed: rear end collisions actually INCREASED in cars with 4 wheel antilock brakes. The theory was that the noise and vibration they make "freaked out" drivers, who released the brakes, then rear ended the car in front of them.
MY ADVICE: Get out on an open stretch of road with no one around and try stopping as hard as you can a few times. Get used to the "ABS experience" so it won't freak you out if the ABS system activates in a panic stop.
If the ABS "kicks in" during a panic stop, don't release the brakes. It should stop you as fast or faster than an "expert driver" in the same circumstance, "pumping his brakes!"
The absolute fastest stop still happens when you are right on the verge of the brakes locking up, but not quite.
For more on ABS check out my article on Anti-lock Brakes.
Thank you for visiting the ECONOMECHANIX WEB SITE. Please feel free to comment. We also serve the surrounding communities of Alachua, High Springs, Hawthorne, and Newberry! Gainesville has been my home since 1974, and I've loved Gvl and the Gators since I came here in the fall of 1974 to attend the University of Florida. I loved it so much I stayed and opened my car repair business. Originally it was out of the back of a 1963 Chevrolet wagon, but in 1977 a fellow mechanic and I opened an auto repair shop with actual walls, etc. I stayed in the same location for 26 years, and recently moved my operation to property I bought 15 miles east of Gainesville. I am doing most all the repairs myself now, having reduced my overhead from $1500 per month to practically nothing. I do work by appointment only. I mostly work only on my established customers cars, but I will occasionally take on new clients. E-mail me and I will either make arrangements to look at your car, or I will recommend you to someone who will.
George G. Scott, Jr.
ABS: Anti-Lock Brake Systems
ADVANCE: Car ignition timing
ALTERNATORS and Car Battery
BAD CAR DESIGNS
Bad Drivers: How NOT to drive
BATTERIES: Auto, Car or Truck
BELTS AND HOSES
BODY AND BUMPER REPAIRS
BRAKE REPAIRS: Car or Truck
Car Washing and Care
CARBURETORS:Car & Truck
CHECK ENGINE LIGHT
CLEANING: Engine Cleaning
CLUTCH REPAIRS: Car & Truck
COMPRESSION: Car Engine
COMPUTER CAR CONTROLS
CV JOINT OR CV AXLES
ELECTRIC WIRING REPAIR
ENGINES: Car & Truck
FILTERS: OIL, AIR, ETC.
FUEL AIR MIXTURE
FUEL INJECTION: Car & Truck
FUEL PUMPS: Car & Truck
GAGES AND "IDIOT LIGHTS"
GASKETS AND SEALS
GLASS: WINDOWS AND WINDSHIELDS
HEADS & HEAD GASKET
HOSES AND BELTS
"IDIOT LIGHTS" AND GAGES
IGNITION TIMING: Car & Truck
AUTO JACKS: lifting cars safely
LEAN "Car runs lean"
LIGHTS: WARNING OR "IDIOT LIGHTS"
Limp Home Mode
NO START: Car Won't Start
OIL: What's right for your car?
OIL LIGHT ON OR GAGE LOW
RADIATORS: Car and Truck
RICH: Car runs rich
SEALS AND GASKETS
SERVICE ENGINE SOON LIGHT
STARTERS: Auto, Truck
TIMING: IGNITION TIMING
TIMING BELT & TIMING CHAIN
WARNING LIGHTS OR "IDIOT LIGHTS"
Car Washing and Care
WATER PUMP REPAIR
WINDOWS AND WINDSHIELDS