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What does the converter dolly do in a doubles combination?
- A.It converts air brakes to hydraulic brakes
- B.It converts a semitrailer into a full trailer by giving it a drawbar and an axle with its own fifth wheel
- C.It turns a van into a tanker
- D.It doubles the engine power of the tractor
Correct answer
B. It converts a semitrailer into a full trailer by giving it a drawbar and an axle with its own fifth wheel
Why
A dolly carries the front of the rear trailer on its own small fifth wheel and connects to the unit ahead by a drawbar. Its air and electrical connections need the same careful checks as any other coupling in the combination.
Manual topic: Combination Vehicles - Doubles · From the General Knowledge practice bank (GK-147).