5th wheel lock?

Locks keep marginally honest people honest. A pro will have any lock off in seconds, if he really wants your FW or hitch. Just make d@mn-sure you have good insurance and don't leave valuables in your FW. If you =must= leave such behind frequently, then check out the various GPS tracking systems.

HEY! There's an idea. Have an OnStar-like device tied to your trailer brakes. Trailer gets stolen? Use a phone app, and lock 'em up. :B Yeah, yeah, brake wires could be cut, but it would mean time that a thief might not want to spend.

Lyle

I use a padlock on the end of the pin that holds the hitch to the rails

It could be meant either way. You can buy a lock that goes on pin of trailer, for trailer theft. You can also lock many hitch handles, so they can not be opened easily by a prankster. In some cases, hitch types, you can lock the hitch to the truck, to prevent hitch theft.

What do you want a lock to do for you?

Jerry

I am curious what lock he was talking about. I always keep a combo lock-locked-on the arm that releases the hitch from the hitch pin when my 5th wheel is hitched. Also, in RV parks that I am not familiar with or doesn't look very secure I have a lock that goes around the King Pin to prevent 5'vr theft. Trailers have been stolen out of Rv.Parks when the owners are not present. Hard to believe but it is true.