Lift axle control and module

A method of making a motor vehicle that has an auxiliary lift axle, the method comprising:

• fabricating an auxiliary lift axle module that comprises an auxiliary axle, brackets proximate ends of the auxiliary axle, air lift springs for raising and lowering the auxiliary axle on the brackets, load air springs, a beam bridging the brackets, pneumatic components mounted on one or more of the brackets and beam, and air lines connecting the pneumatic components, the load springs, and the lift springs to form a operative system for introducing air into and exhausting air from the load springs and the lift springs;
• and
• installing the module in a vehicle by attaching the brackets to a frame of the vehicle, attaching the load springs to the frame, and making electrical and pneumatic connections between the vehicle and the module to render the module operative in the vehicle to raise and lower the auxiliary axle.

A method of making an auxiliary lift axle module for a motor vehicle, the method comprising:

• assembling an auxiliary axle, brackets proximate ends of the auxiliary axle, air lift springs for raising and lowering the auxiliary axle on the brackets, load air springs, a beam bridging the brackets, pneumatic components, and air lines connecting the pneumatic components, the load springs, and the lift springs to form an operative system for introducing air into and exhausting air from the load springs and the lift springs to simulate raising and lowering of the auxiliary axle on the vehicle prior to actual installation of the module on the vehicle.