Texas CDL General Knowledge Practice Exam

What is "double clutching"?

1. A technique to accelerate faster

2. A method of steering while reversing

3. A technique used to change gears by engaging the clutch twice

4. A system for reducing engine noise in heavy trucks

The correct answer is: A technique used to change gears by engaging the clutch twice

Double clutching is a technique used in manual transmission vehicles, particularly in heavy trucks and vehicles that require a significant amount of power and torque. This method involves pressing the clutch pedal twice during the gear shifting process. When performing double clutching, the driver first presses the clutch pedal to disengage the current gear. After this initial disengagement, the driver shifts the transmission into neutral and releases the clutch pedal, allowing the engine to rev. This allows the engine speed to match the speed of the new gear being selected. The driver then presses the clutch pedal again, shifts into the desired gear, and releases the clutch smoothly while applying power. This helps to synchronize gear speeds and makes the shifting process smoother, reducing wear on the transmission and improving vehicle control. In the context of heavy vehicles, where the weight and engine torque can make shifting difficult, double clutching is especially useful for maintaining performance and driving comfort.