Problems with Sebring Brakesby Eli Laurens
The Chrysler Sebring was manufactured with a hydraulic braking system that uses a caliper/pad and drum/shoe setup to stop the vehicle. Later or upgraded models can have four wheel disc brakes. The average backyard mechanic can troubleshoot the Sebring brakes in about 30 minutes.
The Sebring, like most other Chrysler models, had early problems with the anti-lock braking system (ABS) incorporated into the front calipers. The wiring harness connectors and sensors could malfunction and confuse the computer, or cause the calipers not to allow complete braking. The system is designed to prevent wheel lockup during hard braking by preventing the calipers from fully pushing the pads onto the rotor. This can be felt as a "hard pedal", or a lack of stopping power when the brakes are applied. Hard pedal can also be caused by problems with the power booster (in back of the master cylinder), but the ABS system is easier to repair and should be checked first.
Calipers and Pads
As with many other disc brake systems, the inherent design of the rotor/caliper mechanism can lead to several issues: rotor warping, groove damage to the rotor, inexpensive pads causing grinding or squealing, and a loss of pressure due to bad caliper piston seals. All of these problems are alleviated by replacement parts, but could return if the cause is not addressed. Heat buildup from over-braking is the primary cause of braking system failures and damage, and can cause most of the issues listed. Poor manufacturing or obstruction from debris can cause grooves in the rotor (as the pads continue to scratch the friction surface), cutting large gashes that cannot typically be repaired except by total replacement.
Damaged parts and a buildup of heat can break down the hydraulic fluid that is in the caliper, brake lines, and master cylinder. The fluid, DOT-3 for the Sebring, will go from a golden-yellow color to a dark brown or black when the particles are damaged from heat. A complete purge of the braking system is required, to replace all of the fluid. Usually, the caliper pistons are at fault, as the pads heat up they come closest to the fluid at the piston. This "cooks" the fluid, and as it is retracted back into the system (as it cools or the brakes are released), it causes the heat to travel into sensitive areas of the system. The seals in the master cylinder and power booster are prone to damage from heat. The fluid will lose its ability to maintain pressure, as it introduces air into the system and compresses.
Using ceramic pads instead of the semi-metallic types that came on the Sebring from the factory can reduce noise and increase the braking system's lifespan. Semi-metallic pads are usually produced as the cheapest, lowest common denominator of brake pads available. Ceramic pads are about 50% more money to purchase, but they do not wear as quickly, reduce heat buildup, and do not typically squeal.
The Sebring's rotors are the same models used on many other Chrysler products, and while parts are less expensive, they are not ideal brakes for the car. Aftermarket brakes with larger rotors and calipers are manufactured to a higher quality, and will perform much better under stressful conditions. The larger rotor normally has air vents cut into it, and these are designed to reduce heat buildup. Larger rotors require larger calipers and pads, and these usually come as a kit.
Eli Laurens is a ninth-grade physics teacher as well as a computer programmer and writer. He studied electrical engineering and architecture at Southern Polytechnic University in Marietta, Ga., and now lives in Colorado.