Coupling & UncouplingQuestion 11 of 60
During uncoupling, when should you lower the landing gear?
a.After pulling the tractor completely out
b.Only if the trailer is empty
c.Before releasing the fifth wheel locking jaws, until it makes firm contact with the ground
d.At the same time you pull the fifth wheel release handle
Explanation
You should lower the landing gear until it makes firm contact with the ground before unlocking the fifth wheel. If the trailer is loaded, turn the crank a few extra times to lift some weight off the tractor. This prevents the trailer from dropping suddenly when the tractor pulls out.
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Related questions on this topic
- After the trailer is securely coupled and supported by the tractor, what should you do with the landing gear?
- Before supplying air to the trailer, why should you check the trailer brakes are set?
- When you push the trailer air supply valve in (supply air to trailer), what should happen?
- 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?
- After unlocking the fifth wheel jaws during uncoupling, how should you move the tractor?
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