During the extra walk-around checks for a combination with a sliding fifth wheel, what two things does a driver verify?

Explanation

The driver has two things to verify: every locking pin is seated and locked, and the fifth wheel is positioned far enough back that turning the rig won't bring the tractor frame into the landing gear or swing the cab into the trailer. Those are two different failure modes arising from one adjustment: unlocked pins let the fifth wheel slide while the vehicle is moving, and a fifth wheel set too far forward removes the clearance an articulated combination needs to turn. 49 CFR 383.111(a)(17)(iii) names coupling system defects among the safety-related items every commercial driver must know to look for during an inspection, but it does not list these specific checks, so they are attributed to the manual. The wrong options invert each requirement: the slide should be properly greased rather than grease-free, there is no rule to keep the fifth wheel fully rearward irrespective of load, and removing the locking pins before driving is precisely the condition this check exists to rule out.

Source: 49 CFR 383.111(a)(17)(iii)