CDL Combination Vehicles TestCoupling and UncouplingHard
A driver is inspecting the fifth wheel assembly during a pre-trip inspection. They notice a gap between the upper and lower fifth wheel plates. What is the maximum acceptable gap allowed between the fifth wheel upper and lower plates?
- A1/8 inch.
- B1/4 inch.
- CNo gap is acceptable.
- D1/2 inch.
Show answer & explanationAnswer & explanation
Correct answer: C. No gap is acceptable.
There should be no gap between the upper and lower fifth wheel plates when coupled. A gap indicates excessive wear or improper coupling, which can lead to instability and potential separation.
Why the other options are wrong
- A. This amount of gap is not acceptable and indicates a problem.
- B. This amount of gap is not acceptable and indicates a serious problem.
- D. This amount of gap is not acceptable and indicates a critical safety issue.
Fifth Wheel Plate Gap
The space between the tractor's fifth wheel and the trailer's upper plate when coupled. No gap is acceptable.
- Indicates proper coupling or wear.
- Should be flush when locked.
- A gap is a critical safety defect.
Memory trick: No space, safe place.