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Doubles and Triples Test
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Question #1 of 24

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Should the shut-off valves on the trailers be open or closed on a set of double trailers?


All shut-off valves should be open.

The rear trailer does not have shut-off valves.

All shut-off valves should be closed.

The rear trailers shut-off valves should be open, and the front closed.

The rear trailers shut-off valves should be closed, and the front open.

None of the above.



Doubles and Triples Endorsement Requirements

Each applicant for the doubles and triples endorsement must have knowledge covering procedures for assembly and hookup of the units, proper placement of heaviest trailer, as well as handling and stability characteristics.

The applicant must also be able to identify potential problems in traffic operations, including problems the motor vehicle creates for other motorists due to slower speeds on steep grades, longer passing times, possibility for blocking entry of other motor vehicles on freeways, splash and spray impacts, aerodynamic buffeting, view blockages, and lateral placement as well as operating practices and procedures not otherwise specified.

CDL Test Source: Electronic Code of Federal Regulations.

 

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