CDL Vehicle Combination Practice Test

When coupling a tractor to a trailer, which clearing check is necessary?

1. Ensure there is enough clearance between the trailer tires and the ground

2. Verify the gap between the tractor and trailer is too small

3. Check for clearance between tractor frame and landing gear

4. All of the above

The correct answer is: Check for clearance between tractor frame and landing gear

When coupling a tractor to a trailer, checking for clearance between the tractor frame and the landing gear is crucial for ensuring a safe and proper connection. The tractor frame and landing gear need sufficient space to avoid any contact that could lead to damage or malfunction while the vehicle is in operation. An improper fit could result in the landing gear being crushed or bent if the tractor frame is too close, which can impair the functionality of the coupling and create safety issues during driving. This specific check prevents operational failures and potential accidents caused by the lack of necessary space between these components. Ensuring this clearance also contributes to the overall structural integrity of both the tractor and trailer during transportation. It is important for drivers to conduct this check methodically to ensure their equipment remains in good working condition and safe for use on the road. In contrast, while checking the height of the trailer tires off the ground and the gap between the tractor and trailer may seem relevant, they are not specifically critical checks during the coupling process concerning operational safety and efficiency.