Control & OperationCâu 82 / 120
Why should you check the trailer height and the position of the fifth wheel jaws visually after coupling, even after a successful tug test?
a.A high hitch can appear locked while the kingpin sits on top of the closed jaws, which can pull apart in traffic
b.Visual checks are only needed on flatbed trailers
c.The tug test only checks the electrical connection
d.The jaws cannot be seen from outside the vehicle
Giải thích
A high hitch can leave the kingpin resting above the jaws so the coupling looks secure but is not, which is why the manual requires looking under the trailer with a flashlight. Visual checks apply to all trailer types, the tug test is a mechanical check, and the jaws are visible from beneath the coupling.
Luyện miễn phí toàn bộ 120 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- You are stopped on an upgrade in a manual-transmission truck and need to start moving without rolling back. What is the correct technique?
- How should you hold the steering wheel when driving a heavy vehicle?
- What is the correct way to make a normal stop in a vehicle with air brakes?
- Why should you avoid coasting in neutral while driving a commercial vehicle?
- You need to pull into a truck stop space at night and only a blind-side space is open. What is the safest practice?
- What happens if you turn too sharply while backing a tractor-trailer?
Cập nhật gần nhất: · quy trình kiểm tra
Đội Ngũ Biên Tập PrepPass · Đối chiếu với Commercial Driver's License (CDL) General Knowledge Test · Quy trình kiểm tra