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Why should the fifth wheel skid plate be kept properly greased?
- A.Grease is what locks the kingpin into the jaws
- B.So the trailer can pivot smoothly on it in turns without binding, dragging, or adding steering resistance
- C.Grease prevents the trailer brakes from locking
- D.A dry plate is required for the tug test to work
Correct answer
B. So the trailer can pivot smoothly on it in turns without binding, dragging, or adding steering resistance
Why
The trailer's front rests and turns on the skid plate, and a dry plate makes the trailer resist turning and then break loose suddenly. Proper grease lets the combination articulate smoothly and predictably.
Manual topic: Combination Vehicles - Coupling Inspection · From the Combination Vehicles practice bank (CV-160).