Vehicle InspectionQuestion 18 of 120
You are performing the tug test after coupling. What are you actually checking?
a.That the fifth wheel locking jaws have fully closed around the kingpin and the trailer will not pull free
b.That the trailer brakes release quickly enough
c.That the landing gear is strong enough to hold the trailer
d.That the electrical cord carries enough current
Explanation
With the trailer brakes locked, gently pulling forward proves the coupling is holding the kingpin. The tug test says nothing about brake release timing, landing gear strength, or the electrical circuit, each of which is checked separately.
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