Most of us who have been on the road a long time, were taught to pump the brakes when we felt a skid was imminent, such as on wet or icy roads. It’s still my first instinct in those situations. It’s no longer the “right” thing to do, and i have to fight those instincts to brake properly by today’s procedures in those few instances when i have to hit the binders hard!
A form of computerized control, called anti-lock brake system, or abs, is used on all modern vehicles today. It’s a wonderful technological advancement, which, if we are lucky, most of us never get to use!
In a hard braking or “panic stop”, abs takes over brake pedal control to an extent that it “pumps the brakes” very rapidly and selectively to the front and rear wheels. This prevents one or more of the wheels from locking up, and causing a skid.
To make this system work, a computer or module sends signals to a sophisticated valve assembly with solenoids to control the flow of fluid through each wheel’s brake fluid line.
The fluid pushes the caliper or wheel cylinder which then pushes the friction material against the drum or rotor, and thus slows the wheel.
With all this high tech hardware in your brake system the weak point is the hydraulic brake fluid itself.
Temperatures in the wheels can reach hundreds of degrees in hard braking or repetitive braking situations, and liquids have a tendency to “boil” at those temperatures.
Brake fluid is a hydroscopic fluid. It absorbs water right from the atmosphere. Water lowers its boiling point and repeated high temperature peaks break down its hydraulic capability.
All car manufacturers recommend changing your brake fluid on a regular basis. most owners never do it, unless it is explained and recommended to them.
Oh by the way, replacing a corroded or rusted abs valve assembly can cost between $1200 and $2500! Here at Chino Autotech, we use a chemical strip test to determine the condition of your brake fluid. we also often use a tester which heats the fluid to its boiling point to determine how much water it has absorbed.
The boiling point of “good” dot 3 fluid is 401 degrees Fahrenheit. Only 3% of water in the fluid drops the boiling to 284 degrees!…Not nearly high enough.
We at Chino Autotech recommend our Wynn’s smart bleed service. all old fluid is removed, flushing the system completely. All hydraulic brake parts are checked for leaks, and new premium quality brake fluid is installed. Brake adjustment is performed on drum brakes, and friction material is inspected for wear.
It’s spring, and hot weather driving is right around the corner in chino and chino hills. Get your car ready with a brake safety inspection and a brake system flush if necessary.
Remember, you can’t set a price on peace of mind or the motoring safety of your family.
Final tip:
The correct thing to do in a panic stop if your car or truck has abs?
Depress the brake pedal very hard, while steering your car in the safest direction for the situation, and don’t pump the brake pedal, or let up, until you are safely stopped or out of danger.
This is Jim O’Neill, for Chino Autotech, and your local Adelphia cable system.
Jim O’Neill
Chino Autotech Inc.,
Auto Club of SoCal Approved Auto Repair Facility
Auto Value Certified Service Center
NASTF Service Information/Communications Committees
ASE CMAT-L1, CA. Smog Check Technician
AMI AAM Accredited Automotive Manager
Northwood University-University of the Automotive Aftermarket-Leadership 2.0, Class of 2008-2009