When coupling, the glad hands are used to connect:

The service and emergency air lines from the truck to the trailer.. Section 6.2: Glad hands are coupling devices used to connect the

When coupling, the glad hands are used to connect:

ANSWER BREAKDOWN
  • A. Incorrect. "The electrical lines." is not correct. Glad hands are coupling devices used to connect the service and emergency air lines.
  • B. Correct. Glad hands are coupling devices used to connect the service and emergency air lines.
  • C. Incorrect. "The kingpin to the fifth wheel." is not correct. Glad hands are coupling devices used to connect the service and emergency air lines.
  • D. Incorrect. "The safety chains." is not correct. Glad hands are coupling devices used to connect the service and emergency air lines.