Foot brake and handbrake are effectively the same thing because they operate on shared friction components using mechanical wires instead of hydraulic lines. Th

Foot brake and handbrake are effectively the same thing because they operate on shared friction components using mechanical wires instead of hydraulic lines. There maybe a different mechanism but it ultimately uses the same drum or disc. Engine braking (jake braking) by trucks is illegal by statue in many cities and towns because it's very loud. Also, engine braking is riskier in terms of costs (stresses to drivetrain, torque converter, transmission, engine) than brake pads, so people aren't going to do it. Furthermore, they rarely have the skills or transmission to be able to do it conveniently. In addition, if it were more efficient or safer, it would likely be a feature, but I've never seen it in a standard transmission passenger vehicle.