Coupling & UncouplingQuestion 22 of 60
If the trailer is too low when you back under it, what is the likely result?
a.The kingpin locks perfectly
b.The tractor may strike and damage the nose of the trailer instead of coupling
c.The landing gear rises automatically
d.The glad hands connect themselves
Explanation
If the trailer is set too low, the tractor frame or fifth wheel can hit and damage the front of the trailer rather than sliding underneath. If it is too high, the tractor may pass under without the kingpin engaging the fifth wheel. The trailer should be just low enough to be lifted slightly during coupling.
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Related questions on this topic
- What should you check about the fifth wheel plate before backing under a trailer?
- Before coupling, why should you inspect the area around and under the trailer?
- Which of the following is the correct sequence when coupling a tractor and trailer?
- What is the purpose of the safety catch on many fifth wheel release levers?
- Why must you supply air to the trailer and check for air leaks before moving after coupling?
- When should you chock the trailer wheels during coupling or uncoupling?
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