hitches

craig we have tried raising and lowering the unit. when the king pin is in the jaws the jaws are closed but the handle does not snap closed.

The curt hitches are very height concerning. The king pin has to be at the correct height to have the jaws close. It does not help to raise and lower unit while king pin is in the jaws. Pull truck out and either raise or lower unit alittle. Then back in again. Also have you put grease into the zerks lately, or as said on another post removed old grease. I have had many trouble free years with my q5

Could be height of kingpin is not allowing jaws to drop. I had to back mine in a few trys in the past to lockup. Could by caked on grease or not enough in the lock mech.

Just looked at the Curt website at the Q20k hitch. It says;

Out of sync jaws - Do not couple
Flip lock seated in second groove.
Red dot will be visible from cab side
Jaws open
Jaws are partially open and interlocked
Lock bar fully extended
WARNING: Do not couple. The jaws are semi-open and
interlocked/interlaced with each other. The lock bar is
somewhere in between full, retracted position and full,
extended position. This configuration means that the movable
jaw has become out of time with the second fixed jaw.
Inspect that the flip lock is hanging
free in its clockwise, rotated position.
Pull the lock bar to its full, extended position
and release. The jaws will re-time themselves.
Visually check that jaws are open and ready
to receive trailer's kingpin (yellow dot).

More to see https://www.curtmfg.com/masterlibrary/16130/installsheet/CM_16130_INS.PDF

Is this your first time with the hitch?Or newer truck?
If so like David said proper height needs to be adjusted.
Had this issue .Had to raise my hitch all the way up.
Now when I unload all I do is raise it up enough to see a little light between the hitch and pin

I measure the height so I never have to guess how height again.

proper height?