MARF75 wrote:What about a Mico lock like used on heavy equipment?
I think if you check DOT rules you will find emg brakes are to be mechanical for OTR vehicles without air brakes.
In all my years of being under vehicles I can only remember one type of vehicle without mechanical brakes. That was chevy 4500's used by schamns. Their E brakes is applied by a linier actuator. If it looses power. It will apply automatically it is controlled by the PCM. .