Home › CDL Practice Tests › General Knowledge Questions › Question 148
When coupling a second trailer in a doubles set, why is the order of units important?
- A.The longer trailer always goes last regardless of weight
- B.Order has no effect on handling
- C.The lightest trailer belongs right behind the tractor
- D.The heavier trailer should generally go directly behind the tractor and the lighter one at the rear for stability
Correct answer
D. The heavier trailer should generally go directly behind the tractor and the lighter one at the rear for stability
Why
A heavy rear trailer behind a light front one can push and sway the combination, especially in wind and braking. Building the set heavy-first keeps the train tracking straight instead of wagging from the back.
Manual topic: Combination Vehicles - Doubles · From the General Knowledge practice bank (GK-148).