Tech Tip: Rear Axle Load Valve Causes Low Pedal

Tech Tip: Rear Axle Load Valve Causes Low Pedal

The mechanical linkage and the valve cause problems on some trucks by leaking and increasing braking distances. The main culprits are rust and corrosion.

Models: 1995-2004 Tacoma

One problem area is the load-compensating valve that attaches to the rear axle. The mechanical linkage and the valve cause problems on some trucks by leaking and increasing braking distances. The main culprits are rust and corrosion. The valve is designed to change brake hydraulic pressure in the rear brakes as the load changes the relationship between the body and the axle. Some techs have reported the spare tire can come in contact with the linkage if the carrier mounting points fail due to corrosion.

When replacing the unit, it’s critical to adjust the linkage. On 2WD trucks, make sure there is 78 mm of distance between the center of the bolt on the axle shackle, and the center of the bolt on the arm that connects the linkage to the valve. On 4WD trucks, that distance should increase to 120 mm.

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