Why should you always chock the trailer wheels or apply the trailer brakes before starting the coupling process?

Pick an answer

1. Chocking is only necessary when uncoupling, never before you start coupling a trailer
2. It is required only for trailers heavier than 40,000 pounds
3. It has no effect on how safely coupling can be performed
4. It prevents the trailer from rolling while the tractor is backing up to it

Correct!

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