At what point in uncoupling do you lower the landing gear?

• A.Never, if the trailer is loaded
• B.Only after the tractor has driven away
• C.After positioning the trailer and before pulling the fifth wheel release, with the gear down and its feet firmly taking the trailer's weight
• D.After disconnecting nothing else matters

Why

The gear must be down and firm before the tractor pulls out, or the nose of the trailer will drop. Lowering it after you have parked straight, chocked if needed, and set the trailer brakes keeps the trailer stable when the fifth wheel lets go.

Manual topic: Combination Vehicles - Uncoupling · From the General Knowledge practice bank (GK-138).

Practice this subject as a full test

More Coupling Basics questions

• Before backing under a semitrailer, what should you check about the trailer height?
• What is the purpose of the tug test right after coupling?
• After coupling, why must you get out and visually inspect the fifth wheel jaws and release handle?
• What danger does a gap between the trailer apron (upper coupler plate) and the fifth wheel plate indicate?
• When connecting the air lines, why do you connect the glad hands with the seals facing each other and turn them about a quarter turn?