Coupling & UncouplingQuestion 24 of 60
When should you chock the trailer wheels during coupling or uncoupling?
a.Never, the fifth wheel holds the trailer
b.Only on flat ground
c.Only when the tractor is attached
d.When you are not sure the trailer spring brakes will hold it, such as an empty or brakeless trailer
Explanation
You should chock the trailer wheels whenever you are unsure the trailer will stay in place, such as a trailer without spring brakes or one parked on a slope. Chocks keep the trailer from rolling during coupling or uncoupling. This protects you from a runaway trailer while you work between the units.
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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?
- If the trailer is too low when you back under it, what is the likely result?
- Why must you supply air to the trailer and check for air leaks before moving after coupling?
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