If you start noticing that your car is starting to pull to one side, or you smell burning, one or more of your brakes could be binding or seized. Fear not! We’ll help you diagnose and fix it…

What are the symptoms of a seized brake caliper?

There are several reasons why brakes drag or bind, but it is typically because something in the system has seized or become stuck. The piston can stick within the caliper. Brakes pads can get skewed and seize. On single-piston calipers, sometimes the slide pins seize. Finally, if a car is allowed to sit in a damp environment, the pads can actually become stuck to the disc.

If a brake becomes seized when the vehicle is unused, the symptoms are obvious – when you try to drive it feels like the brakes are on! Sometimes it is so bad the car won’t move at all.

If it is the caliper slide pins that have seized, the car may appear to drive normally, but the pads will only be pushed onto the disc from the piston side. This will give reduced braking ability on one wheel and wear the pad on the piston side much faster. In cases like these, the car may pull to the opposite side when the brakes are applied.

If the piston is stuck within the caliper, or the pad is stuck, the car can feel down on power (as if the parking brake is on). You may also notice the car pulling to one side with the steering wheel pointed straight, when cruising and not applying the brake.

As you drive, the seized brake may also get hot – very hot. You’ll quickly smell the brakes overheating (it’s a distinctive acrid smell) and may even see smoke coming off them. If this occurs, stop! Driving with a badly binding brake can generate enough heat to start a fire, but even if it doesn’t you can damage the discs and any component connected to the wheel hub.

In many cases, the brakes binding on one wheel will happen so gradually that you don’t notice the difference. It may only become apparent in your state’s yearly safety inspection when they test the brakes for proper function, and straight stopping.

Unsticking a Seized Brake Caliper

If the cause of your brake issue is the parking brake cable/mechanism, a skewed pad, or the pads sticking to the disc, the remedy is fairly simple. Lubricating the parking brake system should fix that issue and removing the pads and applying a small amount of grease to the edge should fix skewed pads. Once stuck pads have been freed from a disc, the solution is resurfacing the disc and replacing the pads

Brake caliper rebuild vs replace

Even if you free a stuck brake, there is a high likelihood of it seizing again if it was caused by the caliper piston, or slide pins. The corrosion that caused the unit to get stuck is still there, and it is only a matter of time before it sticks again. Replacing the bad caliper is always an option, but often it can be rebuilt for less money.

You may want to buy a good used caliper and rebuild it with new seals instead, if yours is badly corroded. But remember, a junkyard caliper could even be worse than the one you’re replacing!

If your wallet allows, the simplest, and wisest option is always a brand-new caliper! Ultimately it comes down to budget.

Have more questions? Give us a call at BMW Repair San Diego. One of our trained technicians can help answer all your questions or get you scheduled for an appointment for repair!