HUB ASSY, WHEE 1C4325 - Caterpillar

Introduction
This procedure should be performed if the machine has a constant drift to one side when operating on level ground with the steering control levers fully released. Step 1. Check for symptom.a. Determine that the symptom is active.b. Complete this procedure only if the symptom is active. Results:* ACTIVE - Proceed to Step 2.* NOT ACTIVE - STOP. Step 2. Check sensors.a. Use the Caterpillar Monitoring System to preform a Steering/Brake Sensor Quick Check.Reference: Refer to Power Train Electronic Control System, SENR8367, "Component Data Display Mode" for additional information. Expected Result: The sensors operate properly. Results:* OK - Proceed to Step 3.* NOT OK - Replace the faulty steering/brake sensor. Check the operation of the machine for the original complaint. If conditions are not resolved, proceed to Step 3. Step 3. Check clutch pressure.a. With the parking brake disengaged, check the clutch pressure at the steering and brake control valves. Use pressure tap (G) for the left hand clutch and pressure tap (H) for the right hand clutch.b. Inspect the solenoid electrical connectors for damage and/or wear.Reference: Refer to Power Train Electronic Control System, SENR8367, "Connector Inspection" for additional information.
Figure 1: Steering and Brake Control Valve (11)
(F) Steering clutch (left). (G) Brake (left). (H) Brake (right). (J) Steering clutch (right). Expected Result: The pressure should be 2240 150 kPa (325 22 psi). Results:* OK - Proceed to Step 8.* NOT OK - Proceed to Step 4. Step 4. Check system pressure.a. With the parking brake disengaged and the machine in high idle (2245 30 RPM), check the system pressure at transmission main relief valve pressure tap (E).
Figure 2: Transmission Pressure Taps
(15) Transmission. (E) Transmission main relief. (L) Transmission lubrication. (M) Oil temperature. Expected Result: System pressure should be 3100 150 kPa (450 22 psi). Results:* OK - Proceed to Step 6.* LOW PRESSURE - Proceed to Step 5. Step 5. Perform Low Power Train Oil System Pressure. Results:* OK - Proceed to Step 6.* REPAIRED, OK - STOP. Step 6. Swap pilot valves.a. Interchange the pilot valve that should be engaged with the one that should not be engaged.b. Verify whether the problem changes sides ((LL) left hand valve and (RR) right hand valve)..
Figure 3: Steering Solenoids
(LL) Left hand steering solenoid. (RR) Right hand steering solenoid. Results:* CHANGES SIDES - Proceed to Step 9.* DOES NOT CHANGE SIDES - Proceed to Step 7. Step 7. Manually inspect the clutch/brake valve.a. Disassemble and inspect the clutch/brake valve for failure.b. Repair as required.c. Calibrate the steering clutch/brake modules using the procedure