Air brake adjustment is a critical factor in achieving optimum system performance. Brake chamber stroke must be minimized if maximum brake torque is to be achieved. A significant loss of brake torque occurs over what is considered to be the acceptable brake adjustment range particularly if the brake is hot. A large number of air braked vehicles on the road have brakes out of adjustment or have brakes considered to be in adjustment that are operating at a reduced effectiveness level. Better adjustment maintenance would improve truck safety.