303.02.0034.01 Repair Kit for 4-Circuit Protection Valves

What is a 4-circuit protection valve repair kit?

A 4-circuit protection valve repair kit restores the functionality of the pneumatic valve that distributes air pressure into four independent circuits: front axle, rear axle, parking brake, and auxiliary consumers. By replacing internal wear parts, this kit helps maintain the integrity of the air brake system in heavy commercial vehicles.

Compatible vehicles and engines

These kits are compatible with WABCO systems used in a wide range of heavy vehicles. Fitment includes Volvo models such as FH13, FM12, and VNL with D13 or D12 engines, as well as Renault Trucks Premium and Magnum models featuring DXi11 or DXi13 engines. It is also fitted to Mack Granite and Pinnacle trucks.

Maintenance and installation guidance

For successful maintenance, technicians should verify the valve housing part number and the vehicle chassis number to ensure correct circuit priority and pressure balance. Replacing seals and diaphragms during scheduled service prevents air leaks from draining critical braking circuits. Consult your authorized distributor for compatibility details.