Reese 5W hitch jaws not locking...?

Unexpectedly, going to move our 5W from FLA back to Kentucky. 5W had been on permanent site here so we never carry our hitch (space issue). Found a used hitch locally. Problem or WORRY? When hitching up my rig with my slider hitch at home, release bar slides out, slides back in, and appears to lock in place, then I close the small swivel lock on the release handle. The used unit I bought doesn't appear to lock the hitch jaws, prior to closing the swivel lock. Takes several connection attempts before the hitch locks on its own. Have had the slider since 2000 and it's one of those things you do so often, you become automatic in the process. Then, when things work differently, you begin wondering is this how it's supposed to work or not? Do not wish to loose a unit on I-75!