What occurs when a load sensing proportioning valve functions properly?

When a load sensing proportioning valve is functioning properly, hydraulic pressure increases at the rear wheel cylinders when the vehicle is loaded. This mechanism is important for maintaining balance and stability when braking.

When a vehicle is loaded, the weight distribution changes, typically increasing the load on the rear wheels. The load sensing proportioning valve detects this change and adjusts the hydraulic pressure delivered to the rear brake cylinders accordingly. By increasing the pressure at the rear with the added load, the valve ensures that the rear brakes can engage effectively, providing better control and preventing the rear wheels from locking up during a stop. This is crucial for maintaining traction and stability while braking, especially in a heavier vehicle.

The proper function of this valve contributes to the overall safety and effectiveness of the braking system, ensuring that the vehicle stops progressively and evenly, without losing control due to uneven brake force distribution.