Free CDL Practice Test Questions | Commercial Driver's License

Question # 70

What is the purpose of the tractor protection valve?

Options:

To keep fuel from leaking

To protect the tractor’s air system if the trailer air line fails

To secure the fifth wheel

To prevent trailer sway

Viewing question 70 out of 72 questions

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Name	Commercial Driver's License
Code	CDL
Vendor	Career
Certification	Federal Motor Carrier Safety Administration

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