Brake Rotor Replacement
The brake rotor provides the friction surfaces for the brake pads to rub against. The brake rotor is the largest and heaviest component of the disk brake system. The rotor is usually made of cast iron because of its excellent friction, heat and wear properties.
There are two basic types of rotors. Solid rotors are most often used on the rear of vehicles equipped with four-wheel disk brakes. Vented rotors have radial cooling passages cast between the friction surfaces.
The experts at Hollenshade’s in Towson can address any problems you may experience with your vehicle’s brake system. Please CONTACT US for an appointment or to ask us a question about brake rotor replacement for your vehicle. Below are descriptions of brake system issues that require brake rotor replacement.
Pulsation and Brake Rotor Runout
Excessive lateral runout in a brake rotor may cause a few unwanted driving sensations. Most common is a pulsation or ‘shimmy’ when braking at higher speeds. Although the expression ‘warped rotors’ is still prevalent when talking about brake pulsation issues, the real culprit of brake roughness isn’t always rotor warping, but rotor-thickness variation. Even rotor thickness variations as little as 0.0008″ can generate noticeable symptoms. Another sensation is ‘judder’ or roughness. This condition can be experienced both cold and warm. Cold roughness develops under normal driving conditions (low brake temperatures), and manifests as pedal pulsation and sometimes steering wheel shaking. Warm roughness occurs with higher-energy braking events generating temperatures in excess of 700 deg F. Localized thermal expansion of the rotor develops into uneven wear of the rotor but also leads to speed related variations in friction force.
Rotor and Hub Surface
Pulsation can result from a brake job completed with the installation of new pads and rotors if the mating surface between the brake rotor hat and hub face is not completely free of rust and scale buildup. A technician installing new brake rotors should always allow time to clean and resurface the hub face and around the wheel studs.
Unequal Pad Contact
If part of the the rotor surface does not appear shiny, where the brake pad and rotor are to make contact when the brakes are applied, a problem with one or more brake system components is likely. Sometimes this condition can indicate an issue with the fitment of the brake pads into the brake caliper bracket or a seized caliper slide pin. Other times it can be a hydraulic issue or a failed brake caliper. A proper brake inspection, by an experienced mechanic, should be performed prior to replacing any components or opening hydraulic lines. Please CONTACT US and we will be happy to schedule you for a brake system inspection.