Home › CDL Practice Tests › Combination Vehicles Questions › Question 24
Why keep the fifth wheel plate properly greased?
- A.Grease lets the trailer pivot smoothly on the plate and reduces wear and binding in turns
- B.Grease holds the kingpin in the jaws
- C.More grease means you never need to inspect it
- D.Grease is only for appearance
Correct answer
A. Grease lets the trailer pivot smoothly on the plate and reduces wear and binding in turns
Why
The apron turns on the fifth wheel plate with every curve. Dry metal binds and wears, making steering heavier and wearing a groove into the plate.
Manual topic: Combination Vehicles - Coupling · From the Combination Vehicles practice bank (CV-024).