Practice question

On the South Carolina CDL combination test, what is the proper sequence for uncoupling?

Release fifth wheel, lower landing gear, disconnect air, drive away
Position trailer, apply trailer brakes, lower landing gear, disconnect lines, release fifth wheel lock, drive away
Drive forward, then back up, then release the lock
Disconnect air first, then back under to release

Answer: B — Position trailer, apply trailer brakes, lower landing gear, disconnect lines, release fifth wheel lock, drive away

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