We had a client come in with a parking brake that was staying stuck on. This obviously was causing all sorts of issues:
It was dangerous as the parking brake was applied at all times – even while driving around, changing the driving dynamics of the vehicle.
It was causing aggressive wear and tear on the parking brake shoes and rear brake disc. That would have destained the brake shoes, and would have spoilt the vehicle’s appearance.
It was causing the parking brake active warning light to stay illuminated while driving – bringing undue stress on the driver. (We all hate ignoring those dash lights!) If you see this we highly suggest towing the car to avoid further damage to the parking brake system.
Upon inspection we discovered that the original gears in the actuator are plastic. Over time the plastic becomes brittle and cracks causing the unit to fail. As a result the actuator was unable to turn the gear and release the parking brake.
7 Series Parking Brake Actuator Recess Located in Trunk
Here we have the trunk of the BMW 745 Li open. We had to remove the spare and the liner to access the actuator.
7 Series Parking Brake Actuator Recess
Here’s a close up of the recess where we removed the actuator.
7 Series Parking Brake Actuator with Gear Removed
Here’s the Actuator itself (with the gears removed.
7 Series Parking Brake Actuator Broken Plastic Gear
Here’s the original gear. It turns like a corkscrew tightening and loosening the parking brake cables. You can see the plastic gears chewed themselves up and broke.
7 Series Parking Brake Actuator Stronger Metal Gear
Now here’s the special part. Using a combination of ingenuity, experience, and a career building strong connections (read Google search), our technicians not only found a fix that cost our client less than replacing the whole unit, but less than the standard plastic replacements. On top of that the metal gear will last much longer than any plastic replacements. Hopefully meaning this issue is fixed for good!
7 Series Parking Brake Actuator Plastic and Metal Gear
Here’s a comparison of the plastic and metal gear pieces.
We’d love to hear your thoughts on the modernization of systems that may not need updating. Like the electronic parking brake with motors and gears vs. a standard lever actuated parking brake. Also, what (if any) “better than OEM” replacements have you found?