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Question
What is the Johnson bar?
Answers
A.  A hand valve that works the trailer brakes
B.  A valve that indicates the fuel level
C.  A valve that limits the amount of cargo
Explanation
The trailer hand valve, also called the trolley valve or Johnson bar, is used to work the trailer brakes. It should be used only to test the brakes. Using it while a vehicle is in motion could cause a skid.
Answer Statistics
13.27 % of our users get this question wrong.
This question's difficulty is Medium

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