I have been selling and installing alarm systems on cars and trucks for 25 years. And because I also sell truck accessories, most of my alarm customers drive trucks. So here are a few things I have learned along the way about protecting your truck and its contents.
Most quality alarm systems on the market today when installed by a skilled installer will give you the basic protection you need to serve as a starting point for a pickup truck security system. But unlike a sedan style car which the standard alarm system protects very well, pickup trucks generally have several other areas of concern that need to be considered. A few concerns may include a toolbox with hundreds of dollars of tools in it, your tailgate probably can be removed without any tools, your spare tire is on the outside of the vehicle, or you have a bed cover with valuable cargo underneath. We can talk about how you protect your truck with a few of these scenarios in mind.
Let's start with the tailgate. The tailgate on most trucks can be removed without any tools... meaning a thief can walk off with yours in minutes and you or your insurance company are left looking at close to $1000 to replace it. So in my opinion, every truck needs a tailgate lock. Some trucks come with them, but most still don't. What kind of lock depends on how you use your truck. They basically come in two varieties. The first locks the handle so the tailgate can not be opened and since you have to lower the tailgate to remove it from the truck, these are pretty effective at preventing tailgate theft. An add on lock to the existing tailgate handle is available for most trucks without dramatically changing the tailgates looks for $50 or less. The are even electronic ones that automatically lock the tailgate when you lock your truck doors and unlock it when you unlock the doors. The second type of tailgate lock secures the bottom hinge to the truck bed, so the tailgate can not be removed. You may have seen people put a hose clamp around the bottom hinge of the tailgate to keep it from being removed easily, and that is basically the idea for these types of tailgate protection, just more secure and high tech. These are a couple types of locks that go around the hinge that work well, and there are also hardened steel plates that cover the gap where the tailgate slips out and secure with a security type bolt. These types of locks are generally $30 or less. The advantage to these types of locks is that they are always there protecting the tailgate without you doing anything once they are installed. But they do not keep the tailgate from being lowered, so if you have a bed cover and want the whole back end of the truck locked, you probably want to consider the type of tailgate lock that locks the handle.
Next let's talk about your spare tire. Suffice to say when you really need it, you expect it to be there and that's not a good time to find out someone stole it. Most trucks being sold today have a full size spare tire under the bed, making them an easy target for theft. Most hang from a manual winch mechanism that raises or lowers them. An easy job to walk up with the right tool and lower down the tire and walk away... even on some new trucks that have a coded tip for the lowering tool because they are not exactly high tech anti-theft equipment. What I recommend here is a heavy steel cable and waterproof lock with the cable run around the truck frame and through the spare tire. Think of a bicycle type lock except since it is under the truck it will get plenty of water and grit on it so make sure the lock is waterproof and preferable has some sort of cap over the key hole, so that lock works well when you need it to. There are also vehicle specific locks that hang through one of the lug holes on the tire that work well, but you generally are going to have to lay on your back under the truck to remove them when the time comes. Choose a plastic coated cable so you don't create a rattle in the back of the truck.
Protecting under the hood can be important as well in some situations. If a thief can gain access to under the hood, he can then disable the siren or battery to get around the alarm system. Most trucks are not easy to get the hood open without releasing it first from the inside, but there are some that can be opened easily. In my experience, many Chevy and GMC trucks can be opened with just a coat hanger through the grille by an experienced person and so extra protection may be needed. There are hood locks and metal guards that can be installed. A good option is a pin switch on the hood to trigger the alarm system if the hood is opened. Another good option is a battery backup for the alarm system, that will keep it operating even if the vehicles battery is disconnected.
Protecting the door handles and locks is vitally important on today's trucks. In my store, in dealing with the aftermath of vehicle break ins, we very seldom see broken windows any more. The preferred way to break into today's trucks is through the door handles. This is because in most cases the handles are made of plastic and screwdrivers and such can be forced in around the edges to manipulate the rods that unlock or open the doors. And often times the actual lock cylinder is pushed back through it's plastic housing and then it can be manipulated with a screwdriver to unlock the door. If you have an alarm system, when the door opens the alarm will trigger, but it only takes a few seconds for a thief to grab your gear and be gone. So I recommend steel plates on the inside of the door handles that protect that vulnerable area of the door. The most common brand is called Jimmi Jammers. These install on the interior of the door behind the door handle and in most cases prohibit someone from successfully breaking in through the door handles. Does not mean they won't try and tear up your door, but chances are they won't be successful at getting in. Many people also replace their door handles that have key cylinders in them with rear or passenger door handles without a keyhole, and just use their remote control to unlock the doors. This is fairly effective, but you need to consider what you will do in the case of a dead battery before you do this.
Now on to protecting tool boxes, tonneau covers, and camper shells. In my experience, a properly installed old fashioned pin switch is the best protection in most cases. Care needs to be taken as to how the wiring from the pin switch is run as it needs to be concealed or it will do you no good. Other choices could be a mercury tilt switch on a cover that raises from one side or a radar or microwave sensor to detect movement inside the cover. I still think a pin switch is the best choice when properly installed as far as providing proper protection and freedom from false alarms.
So, an alarm is just the first layer of security if you own a pickup truck. Consider these other areas and you can have the whole package when it comes to keeping your truck secure.