The height-sensing
proportional valve provides two different brake balance
modes to the rear brakes based on vehicle load. This
is arcomplished by turning the valve on or off When
the vehicle is not loaded, hydraulic pressure is reduced
to the rear brakes. When the vehicle is canying a full load,
the actuator lever moves up to change the valve's setting.
The valve now allows full hydraulic pressure to the rear
brakes. The valve contains a plunger,.cam, torsional
clutch spring, and an actuator shaft (Figure ,{6-1S