If you cannot complete your turn without entering another traffic lane you should:

Question

Accepted Answer

B: Turn wide as you complete the turn.. If you cannot use an off-track maneuver to make a turn, then turn as wide as possible by allowing the truck to move as far forward as possible before starting to turn to give more room for the trailer to clear the turn.

If you cannot complete your turn without entering another traffic lane you should:

Iowa CDL Combination Vehicles Test Info