Description - Proportioning Valve (Height Sensing)

DESCRIPTION - PROPORTIONING VALVE (HEIGHT SENSING)

NOTE: Only vehicles without antilock brakes (ABS) have a proportioning valve. Vehicles with ABS utilize electronic brake distribution which is controlled through the ABS integrated control unit.

Vehicles not equipped with ABS use a height sensing proportioning valve. It is mounted to the body of the vehicle above the rear axle (Figure 1). It has an actuator lever that attaches to the rear axle and moves with the axle to help the valve sense the vehicle height.


CAUTION: The height sensing proportioning valve is not adjustable. No attempt should be made to adjust it. It is replaced as a complete assembly.

CAUTION: The use of after-market load leveling or load capacity increasing devices on this vehicle are prohibited. Using air shock absorbers or helper springs on this vehicle will cause the height sensing proportioning valve to inappropriately reduce the hydraulic pressure to the rear brakes. This inappropriate reduction in hydraulic pressure potentially could result in increased stopping distance of the vehicle.




Figure 1 HEIGHT SENSING PROPORTIONING VALVE