Proffessional Car thief
As a professional car thief (Auto Repossessor) I think I have a little insight as to protection for your car from theft. Most car thiefs are kids looking to joy ride. The professionals know all the tricks mentioned above belive me I have seen them all. And if you think that you will hear a professional in your driveway at 3 am and come out with a gun you are sadly mistaken. I have taken thousands of cars from peoples driveways in the middle of the day and the middle of the night who thought just that. Here are some steps that I have personally taken to protect my truck.
1. Have your truck re-keyed, with your vin number, a few bucks, and a few minutes I can have a working set of keys to your truck, not hard to do. I can do it online or dummy up some registration and get it from the dealer. If you re-key your truck the thief will not be able to get a "key-code" and have a working set of keys made. Any locksmith can do this for around $150 bucks.
2. Cover your dash vin number.
3. Hidden kill switches are very effective, but hid them very good. The locktronics thing can be defeated with a paperclip, I carry a magnet with me for the magnet alarms, these are worthless to stop a pro. Do NOT set them up as a fake switch, I see a lot of people use the high beam/turn single lever as a kill switch or a fog light switch or a blank rocker switch on the kick panel. A professional knows these tricks, my ignition kill switch is a rocker switch mounted underneath my amp under the drivers seat and the wires are tied into the amp wires, it looks like a part of the amp, I have never seen it done before. When you splice a kill switch wire into the factory ignition wire bundle use onion tape to tape as much of it as you can (onion tape is impossible to rip, it has to be cut or unwound, which takes time) Cover the onion tape with black electrical tape and put as many zip ties as you can fit the whole length of the bundle of wires (40 or 50), this will slow down the thief big time as he will have to cut off 2 layers of tape and a bunch of zip ties to find where you spliced into the factory ignition wire. Time is the best defence to stop a thief. I saw this trick on a F-150 and it took me over an hour in my shop to bypass his home-made kill switch, and this was with good lighting and proper tools and no pressure of someone coming out with a gun.
4. Disconnect your hood latch opening lever, its hard to disconnect a alarm, siren or battery quickly if you can't get the hood open. I just use a pair of pliers to pull the wire when I need to open the hood.
Just my opinion but I would think that CTD's are not stolen by kids to joy ride, they are professionals with orders looking for CTD's or other full size deisels, lots of money to be made in used parts. I have seen some chop shops here in Modesto that can strip a full sized truck in a day and dump whats left out in the country on the side of the road... ... ...