During a normal stop, which valve is the first to operate?

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Multiple Choice

During a normal stop, which valve is the first to operate?

When you start braking, the system begins by building hydraulic pressure, and the relief valve is the first to respond. Its job is to sense the initial pressure rise and relieve any excess, shaping the pressure ramp so the brakes apply smoothly and without a sudden spike. After that initial relief action, the other valves come into play to fine-tune the braking: the metering valve can delay pressure to certain circuits to balance the bite, the proportioning valve reduces pressure to the rear to prevent lockup, and the check valve ensures one-way flow and maintains booster vacuum. So the relief valve acts first to control that initial pressure surge.

When you start braking, the system begins by building hydraulic pressure, and the relief valve is the first to respond. Its job is to sense the initial pressure rise and relieve any excess, shaping the pressure ramp so the brakes apply smoothly and without a sudden spike. After that initial relief action, the other valves come into play to fine-tune the braking: the metering valve can delay pressure to certain circuits to balance the bite, the proportioning valve reduces pressure to the rear to prevent lockup, and the check valve ensures one-way flow and maintains booster vacuum. So the relief valve acts first to control that initial pressure surge.

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