Georgia Commercial Driver License Practice Test

What is the function of front brake limiting valves?

1. Increase braking power

2. Prevent front tires from skidding

3. Reduce stopping distance

4. Balance weight distribution

The correct answer is: Prevent front tires from skidding

Front brake limiting valves are designed to help prevent the front tires from skidding during braking. When a vehicle comes to a stop or slows down, the weight shifts forward, placing more pressure on the front tires. If too much braking force is applied to the front brakes, it could cause those tires to lock up, resulting in a skid. The limiting valves modulate the amount of brake pressure applied to the front brakes to ensure that they do not exceed a safe level. This helps maintain steering control and stability during braking, allowing the driver to have better control of the vehicle in emergency situations. In contrast, increasing braking power and reducing stopping distance are not the direct functions of these valves. While they may contribute indirectly by preventing skids and maintaining control, that is not their primary purpose. Balancing weight distribution is also not a function of front brake limiting valves; instead, it is influenced by the overall design of the vehicle and load distribution.