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ABS Speed Sensor Service

One of the most common omissions in maintaining a modern Anti-lock Brake System (ABS) is checking out the speed sensors. These sensors are often located at each wheel hub/rotor on four-wheel disc systems. Alternatively, on rear-drum applications, you'll usually find them mounted on the differential housing. Whatever their location, they supply information regarding wheel speed to the ABS computer. Under braking, if wheel speeds are not equal, indicating wheel lockup, the computer modulates the anti-lock feature until the speeds are equal again...

Bleeding Power Steering

Power steering works by way of hydraulic pressure. Fire up some hydraulic pressure in something like a backhoe, and moving giant rocks around is as easy as pulling a few levers. A forklift uses hydraulic pressure to lift pallets full of concrete blocks high onto this shelf or that. This miracle of hydraulic pressure also makes a great deal of the everyday driving experience easier. Turning the steering wheel from left to right in a car or truck is effortless thanks to power steering by way of hydraulic pressure. Things that work by way of hydraulics have no room for pneumatics. Power steering systems are one of these things. Air can be compressed whereas fluid cannot. Air has no place in a hydraulic power steering system...

Brake Bleeding

Brake bleeding is something that no sane person finds enjoyable. It can be messy and often involves bodily contortionism to access the bleeder screws. However, properly bled brakes are one of the most vital services you can perform on your car...

Drum Brakes - Rear Brake Drum Adjustment

Even though four-wheel disc-brake systems are the preferable way to go—or rather, stop—many vehicles still come equipped with front disc/rear drum systems. And while rear brakes only handle about 25 percent of the braking load, they're still a very important piece of the proverbial braking "pie." If they're not working at peak efficiency, the load they're not carrying, and subsequent wear-related problems, gets foisted on the front brakes. Also, if the vehicle's braking system is a bit under-designed to begin with, the results can be dramatic. Brake rotor "hot-spotting" or even surface cracks, brake pad wear or surface "glazing" can develop—part of a vicious cycle that translates to the driver as a vehicle becomes more and more difficult to stop...

Power-Bleeding Brake Systems

Connected to the brake pedal is a rod that pushes a piston inside the master cylinder. When the brake pedal is pushed down that piston pushes brake fluid through the brake lines. Since this fluid has nowhere to go it pushes pistons inside the brake calipers or wheel cylinders. These pistons push brake pads or shoes against the rotating discs or drums and presto—the vehicle stops. Brake fluid, by virtue of being a non-compressible hydraulic fluid, transfers the pressure between the brake master cylinder and the pistons inside the calipers or wheel cylinders...

Replacement Rotors

To get an idea of how the rotors and brake pads work on your vehicle, grab a paper plate and spin it on your finger. As it spins grab it with your other hand. It stops instantly. The spinning plate is your rotor and your fingers and thumb are the brake pads. If the plate was spinning an awful lot faster and you tried to grab it, your hand and the plate would get hot in the process from the friction created. The energy of the spinning paper plate is converted into heat by the process of the hand grab. Not that you could actually spin the plate that fast, but you get the idea...

Replacing Brake Pads

Brake pads should really be called friction pads. Brake pads use a combination of force and friction to slow the vehicle down when the brakes are applied. There are also brake shoes. The difference between the two is that brake pads clamp themselves onto a rotating disc to convert the driving force of a moving vehicle into heat in order to stop the vehicle, whereas brake shoes push out against a rotating drum in order to accomplish the same task...