Axle control valves

Axle control valves. (1) When a vehicle is equipped with an axle or axles that raises or lowers by means of air pressure, spring force or hydraulic pressure, the control valves shall be installed as follows: (a) The control valve that regulates the amount of pressure shall be mounted outside of the driver’s compartment. (b) The control valve that regulates the movement of the axle or axles so as to raise or lower the axle or axles may be in the driver’s compartment. (2) This section applies to vehicles manufactured commencing with the 1998 model year.