Why should you be sure that the fifth wheel plate is greased as required?
Answer: A
To prevent steering problems.
Friction between the tractor and trailer at the 5th wheel coupler can be caused by a lack of lubrication resulting in steering issues. Keep the 5th wheel plate adequately greased at all times.
All choices
- ATo prevent steering problems.
- BTo reduce heat and noise.
- CTo ensure a good electrical connection.
Why the other answers are wrong
B. To reduce heat and noise.
Choice B is wrong because greasing the fifth wheel plate primarily prevents steering problems, not heat and noise.
C. To ensure a good electrical connection.
Choice C is wrong because greasing the fifth wheel plate does not affect electrical connections.
CDL Combination Vehicles Test Info
Questions on Exam
20
Passing Score
80%
Time Limit
Typically 30 minutes; varies by testing location
The Combination Vehicles test content is federally standardized, so this question applies in every state. Age limits, fees, and testing procedures do vary — check your state's CDL requirements.
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More CDL Combination Vehicles Practice Questions
- You are driving a combination vehicle when the trailer breaks away, pulling apart both air lines. You expect the trailer brakes to come on and:
- Which statement is true of turning while hauling a long trailer combination.
- Should the trailer hand brake be applied when a trailer starts to jackknife?
- Glad hands are usually connecting which of these?
- Why should you lock the tractor glad hands to each other (or dummy couplers) when you are not towing a trailer?