Brake Proportioning/Combination Valve: Service and Repair

The proportioning valves should never be disassembled.

1. Raise and support vehicle, then access modulator assembly by removing the battery, tray, tray support bracket and acid shield as described under Modulator Assembly/Service and Repair.
2. Disconnect brake tube fitting at proportioning valve, then remove valve from modulator assembly.
3. Reverse procedure to install, noting the following:
a. Coat proportioning valve O-ring with clean brake fluid prior to installation.
b. Bleed base and anti-lock brake systems separately.