I believe tilt sensors do work, but you may want to try a proximity sensor (I believe that's what it's called). It's basically like an invisible field that forms around your truck so if anything comes within a few feet of it in all directions, it will chirp, and if it stays in his 'field' for too long, it will trigger the alarm.
The only bad thing about these are, if you have stray cats or any type of animals that roam the neighborhood, or parking at a busy parking lot, your alarm will constantly be chirping/going off. Just another suggestion.
Did you have any type of rim locks on these sets of wheels that were stolen? I personally have 2 different types of wheel locks on EACH one of my rims.
Like they all say though, if they want it, they'll get it. Only thing you can do is try to deter them/slow them down enough to catch them in the action. . .then it's hunting season!!
