Home › CDL Practice Tests › Combination Vehicles Questions › Question 56
When uncoupling a loaded trailer, after the gear touches the ground, why add a few turns in low gear?
- A.To raise the trailer as high as possible
- B.To test how strong the crank is
- C.To firmly transfer the trailer's weight onto the gear and slightly lift it off the fifth wheel so the jaws can release
- D.To tilt the trailer forward for drainage
Correct answer
C. To firmly transfer the trailer's weight onto the gear and slightly lift it off the fifth wheel so the jaws can release
Why
Firm contact alone may leave most weight still on the fifth wheel, jamming the jaws. A few low-gear turns complete the transfer and free the kingpin for a clean release.
Manual topic: Combination Vehicles - Uncoupling · From the Combination Vehicles practice bank (CV-056).