Example embodiments relate to triple redundant brake systems for trucks and other types of vehicles. Disclosed systems offer additional redundancy for braking applications by incorporating a third service brake actuator (e.g., a third ECU), which may be installed parallel to the second controller (e.g., a second ECU). In some examples, the third service brake actuator is an electronically activatable pressure valve and can be implemented using pneumatic select-high valves. These valves can be used to perform a mechanical max arbitration between pressure provided by the second controller and the third controller.