36. The fifth wheel locking lever is not locked after the jaws close around the kingpin. This means that:
The coupling is not right and should be fixed before driving the coupled unit.
37. Off-tracking or cheating causes of which of these to follow the wider pass while making a turn?
Tractor towing a 45-feet trailer.
38. The iron trailer supports are up and the trailer is resting on the tractor. Make sure:
There is enough clearance between the tractor frame and the landing gear.
39. When you are uncoupling a loaded trailer you should lower the landing gear until it:
Make firm contact with the ground, then crackly hits a low gear a few turns.
40. What will happen if the air lines are crossed when you hook up to an old trailer?
If the trailer has no spring brakes, you could drive away but you wouldn’t have trailer brakes.