Question 4 of 140

Before uncoupling a trailer, why must you lower the landing gear until it just touches the ground before disconnecting the fifth wheel?

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To make the trailer easier to see at night, which has nothing to do with how the fifth wheel releases
So the trailer stays supported once the fifth wheel releases, instead of dropping suddenly
To reduce wear on the trailer's tires
It is only a cosmetic step with no safety purpose

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Correct answer to question 4 (Combination Vehicles): So the trailer stays supported once the fifth wheel releases, instead of dropping suddenly

Why

The landing gear is what holds the trailer up once it's no longer resting on the fifth wheel, so it must be set before the fifth wheel is released or the trailer's nose will drop.

Updated: November 2026

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Before uncoupling a trailer, why must you lower the landing gear until it just touches the ground before disconnecting the fifth wheel?

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