Why should you pull forward gently to test the coupling after backing under a trailer, before fully trusting it is locked?

Pick an answer

1. It is done only to check tire pressure indirectly
2. Pulling forward has no diagnostic value for coupling security, only the sound does
3. It should be done at full speed to fully test the connection
4. A gentle pull confirms the fifth wheel actually caught and locked around the kingpin

Correct!

Not quite. The correct answer is highlighted.