E-Brake not locking both wheels

[Mbufford]

Hello brilliant builders!

I encountered a small issue today while playing hookie from work to work on my car.

I got my E-Stopp installed with my 2015 Mustang GT rear brakes, cables run, and adjusted to hold the spring lever 1mm off the rear stop (as Ford recommends for the 2015+ GT brakes).

I set up my test bench power supply to operate the system. On both wheels, the spring lever hits the front stop with full contact. The left wheel locks up just fine, but the right wheel can still rotate. I’m not very familiar with these brakes. But it seems to me that if I’m hitting full stops, there’s nothing on the cable end that would help.

Is this one of the occasions where I need to adjust the piston—I can make the tool from one of my old sockets. If not, what can I do?


Thank you in advance for fixing my ignorance!

[michael everson]

Are the brakes bled? Thought I read somewhere that the parking brake wont work right until that is done. I guess the fluid pushes the piston closer to the rotor.
Mike

[Mbufford]

Are the brakes bled? Thought I read somewhere that the parking brake wont work right until that is done. I guess the fluid pushes the piston closer to the rotor.
Mike

I have not run my brake lines yet, so I guess this is an issue I’ll need to figure out after then.

Seems odd that the e-brake would be dependent on fluid pressure—kind of defeats the ability to use the e-brake in the situation of a catastrophic brake failure.

[Lidodrip]

I have not run my brake lines yet, so I guess this is an issue I’ll need to figure out after then.

Seems odd that the e-brake would be dependent on fluid pressure—kind of defeats the ability to use the e-brake in the situation of a catastrophic brake failure.

I don't believe that the e-brake is dependent on fluid pressure, but rather you need to use the brake system (fully bled) to initially set the correct distance of the pads from the rotors. Once the pads are set closer to the rotor they will stay there and the parking brake will work properly even if the fluid then gets drained. The parking brake is a mechanical system.

James