Question 13 of 20
Score: 0/0When coupling a tractor to a semi-trailer and you have backed close but are not yet under the trailer, what should you connect before backing further?
ExplanationBefore backing under the trailer, always connect the emergency and service air lines to ensure the trailer’s braking system functions correctly.
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Did you know? A high, loaded trailer rolls easily — gentle steering and braking is the recurring answer.
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