Coupling & UncouplingQuestion 14 of 60
After unlocking the fifth wheel jaws during uncoupling, how should you move the tractor?
a.Pull forward quickly to clear the area
b.Ease the tractor forward until the fifth wheel comes out from under the trailer, then stop
c.Back up sharply to free the kingpin
d.Turn hard while pulling out
Explanation
You should ease the tractor forward slowly until the fifth wheel comes out from under the trailer apron, then stop with the tractor frame still under the trailer. This keeps the trailer supported while you disconnect lines. Pulling out too far or too fast before the trailer is fully supported can drop the trailer.
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Related questions on this topic
- During uncoupling, when should you lower the landing gear?
- What should you do with the air lines and electrical cord before pulling the tractor away from the trailer during uncoupling?
- When uncoupling, what does pulling the fifth wheel release handle to the open position do?
- Why is it important that the kingpin be properly locked, not just resting on the closed fifth wheel jaws?
- When raising the landing gear after coupling, what should you be aware of regarding the crank handle?
- Why should you use two low-pressure gears when starting to raise loaded landing gear rather than high gear?
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