NC CDL General Knowledge Practice Test 2025 - Free CDL Practice Questions and Study Guide

When brakes get wet from heavy rain, several issues can occur that affect their performance. The most immediate effect is a lack of braking power. This happens because the moisture can create a film on the brake pads and rotors, reducing friction. Friction is crucial for the brakes to function effectively, and when it is diminished, the brakes may not engage fully when applied.

Additionally, as the brake components work to expel the water, there may be a delay in the brakes responding to the driver's input. This delay can lead to a feeling of reduced effectiveness, often described as the brakes being "soft" or less responsive. Therefore, understanding the mechanics of braking and how environmental factors, such as wet conditions, impact performance is essential for all drivers, particularly those operating heavy vehicles.