A parking brake that sticks is a problem of neglect more than wear. Cars that never use the parking brake have cables that seize in their sheaths, and the first time someone sets it on a hill in Dilworth it does not come back. The reverse happens too — a brake that is set every day but has stretched until it holds nothing. Both are fixable in a driveway.
How it works
A lever, pedal or switch pulls a cable — or on newer cars, commands a small motor — that applies the rear brakes mechanically. Some cars have small drum shoes inside the rear rotor hat for this. Others have a lever on the rear caliper that pushes the piston out. Electric parking brakes use a motor on each rear caliper. The mechanical types are what seize.
Stuck on
Symptoms
- The lever or pedal releases but the car will not roll, or drags
- The car pulls, and a rear wheel gets hot
- Grinding or squealing from the back that does not change with the brake pedal
- A parking brake warning light that stays on after release
Causes
The cable has corroded inside its outer sheath and will not slide back. Water gets in at the ends, sits there through a humid summer, and rust does the rest. A caliper lever seizes on its pivot for the same reason. Rear drum shoes can rust to the drum on a car that sat for a while in wet weather — this one often frees with a firm forward-and-reverse move in the driveway, with a bang.
Will not hold
The car rolls on a hill with the brake fully set. Either the cable has stretched and needs adjusting, the rear shoes or pads are worn past the adjuster's range, or the self-adjuster inside the drum has seized. On cars with the small drum-in-hat shoes, those shoes are often forgotten in brake jobs and are the first thing we look at.
There is a middle case as well: the brake holds on the flat but lets the car creep on a real hill. That is usually adjustment, with the shoes or pads still within range, and it is a quick job when it is caught early. Left alone, the driver pulls the lever harder every month, the cable stretches further, and what was an adjustment becomes a cable replacement.
Electric parking brakes
They do not seize in the same way, and they have their own problems: a failed actuator motor on one side, a fault that leaves the brake applied, and a service mode that must be entered with a scan tool before the rear pads can be changed. Doing rear pads on an electric-brake car without retracting the motor damages it. We use the tool; it takes a minute. Our post on what a proper brake job includes touches on this.
The repair
- 1Confirm which part is seized — cable, lever, or shoes — with the wheel off the ground.
- 2Free and lubricate what can be saved. A seized cable rarely can; it gets replaced.
- 3Replace the caliper if the lever is seized on its pivot, since it cannot be reliably freed.
- 4Adjust the system so the brake holds within a few clicks and releases fully.
- 5Check the rear pads, rotors and bearing for heat damage from the dragging.
Most of this is done on site, in a driveway with level ground. See our brake services.
Frequently asked questions
Should I use my parking brake?
Yes, regularly, on automatics too. Using it keeps the cables moving, and it takes the load off the transmission's parking pawl on a hill.
Is a stuck parking brake an inspection fail?
The NC safety inspection checks that the parking brake holds. One that does not, fails. One that drags will fail the brake test too.
Where do you work?
Across Charlotte, Davidson, Monroe and the rest of the metro. Book a visit or call.
Serving Charlotte and Mecklenburg County. Call (754) 236-1714.
We come to you
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Home, office lot, or wherever the car gave up — we bring the tools, the parts, and the scan tool to you across Charlotte & Mecklenburg County. Upfront quote before any wrench turns.