2WD

Fig. 31 Type 6, Load Sensing Proportioning Valve Pressure Gauge Test Connection:

Fig. 32 Type 5, Load Sensing Proportioning Valve Sensor Spring:

Prior to performing the following test procedures, park vehicle on a level surface, ensure vehicle is unloaded and at normal curb height.

1. Install suitable gauge set as shown.
2. Bleed hose and gauge set.
3. Loosen load sensing unit adjusting nuts.
4. While watching pressure gauges, have an assistant depress the brake pedal.
5. Pressure readings should be as follows:
a. When input pressure is 740 psi, output pressure should read 307-377 psi.
b. When input pressure is 1991 psi, output pressure should read 660-774 psi.
c. Output pressure side to side difference should not exceed 57 psi.
6. If pressure readings are as specified, proceed to step 7. If pressure readings are not as specified, replace the proportioning valve and bleed the hydraulic brake system, refer to Brakes and Traction Control/Brakes/Service and Repair.
7. Adjust load sensing spring distance L to 4.07 inch.
8. While watching pressure gauges, have an assistant depress the brake pedal.
9. Pressure readings should be as follows:
a. When input pressure is 1991 psi, output pressure should read 1228-1580.
b. Output pressure side to side difference should not exceed 121 psi.
10. If pressure readings are as specified, proceed to step 11. If pressure readings are not as specified, replace the proportioning valve and bleed the hydraulic brake system, refer to MAINTENANCE PROCEDURES/HYDRAULIC SYSTEM BLEEDING & FLUSHING.
11. Adjust load sensing spring distance L to 3.42-3.50 inch.