In dash GPS

You're stuck with your current radio unless you're willing to spend big bucks at the dealer. In an effort to prevent you from buying a higher-quality aftermarket radio, GM started building the Body Computer into them during the 2002 model year. You can switch to a GM navigation radio but only the dealer can program it to your truck. GM is the only manufacturer that refuses to release the software to the independent repair shops. They want your dollars after the sale.

To add to the misery, whenever a mechanic has a scanner connected to the truck to "talk to" the computers, he has the option of pressing the "lock" button. That electronically locks every computer on the truck to the Body Computer. No one can come up with a valid reason for doing that to you but if the radio has to be replaced in the future, you must also replace every other computer on the vehicle. Some GM cars have 46 other computers!

There's no legitimate reason for any mechanic to press that lock function but if they ever do, there's no way to undo that programming. An inexperienced mechanic might press that button to experiment, not realizing the potential consequences. No one will ever notice the difference until the radio / Body Computer has to be replaced.

To do what? If you mean install a GM navigation radio, you'll have to ask the dealer. I repair and sell original equipment radios at the nation's second largest old car show in Wisconsin, but now all I can work on is Chrysler stuff. GM began refusing to sell radio service manuals and parts after 1994 and Ford did that in 1998. I don't buy or sell GM radios if I can't get the service manual for it. Also, I've never done the reprogramming procedure but I've been to classes where they describe the ordeal. I can't remember about a 2002 model, but the newer cars and trucks must have software installed for any new computer over the internet. Only the dealer can do that. Chrysler and Toyota allow any independent shop to reprogram any computer on their vehicles except the security system for a small fee. Only Hyundai allows anyone access to their web site and software downloads totally for free. Only GM locks everything up and forces their owners to go back to the dealer. That's just one of many reasons GM has been losing their repeat business and Hyundai is gaining market share.

If you're asking about that "lock" procedure the mechanic can do with their scanner, that information comes from a very high-level trainer who specializes in the hard-to-diagnose cars everyone else has given up on. He has friends who are trainers for the manufacturers and their dealership mechanics. When any computer other than the radio / body computer fails, which is real common, just that computer must be replaced and reprogrammed. Someone pressed the "lock" button on a car he was involved with and it had a problem with the Body Computer / radio. When they installed the new one, nothing else on the car worked. That's when they found out the computers were locked to the Body Computer. The interior lights turned on because they were run by the new Body Computer, but there were no dash lights, (the instrument cluster is a computer module), and the engine wouldn't crank because the anti-theft module wouldn't turn on. If it had cranked, the engine wouldn't have started because the Engine Computer wouldn't turn on, ... You get the idea. In the end, they sent the car to the junk yard, all because of one bad computer. All of those other computers were locked electronically to the Body Computer that was removed. They would have had to replace the air bag computer, anti-lock brake computer, heater control computer, instrument cluster, Engine Computer, and each one would have required a separate software download. Each computer can cost as little as a couple of hundred dollars all the way to over $800.00, and it can take up to an hour per computer to install the software. All the old computers are worthless to the salvage yard too because they will never turn on in another car.

Now, to be fair, I learned this three years ago in one of those high-level classes, and I can't remember if that applies to every GM car and truck model, just some models, or which years. For 2002, you could very well still have a basic plug-and-play radio. If you do, and it's the taller radio than they used in 2001 and all through the late '80s and '90s, that model needs to have the vehicle ID number programmed in. THAT can be done by independent shops that have the GM scanner. There might be some aftermarket scanners that can do that function now too. If the dealer does that, it will be part of the installation process. One thing you should ask first is how much you're going to be charged for labor. If they give you a time of one hour, ask around at some independent shops to see if one can program the VIN into the radio, then consider installing the new one yourself. You'll need the navigation antenna too but that should come with instructions on how to mount it. Our local Chevy dealer is a well-known crook. They have a one-hour minimum shop service charge. Found that out from a fellow who had a head light bulb burn out while the car was still under warranty. They replaced the bulb, then told him GM only pays 0.2 hours to replace a bulb, which is typical, but since they had a one-hour minimum, they wanted him to pay the additional 0.8 hour charge! Come to find out besides being the highest pressure sales department, this ripoff is pretty common. No wonder they're losing customers. No other dealership charges additional labor when something is under warranty.

Something else for you to consider is all through the '90s, GM had a 100 percent failure rate on their cd players. I found five bad lasers out of over 2000 Chrysler radios I've worked on for dealers around the state, and only one or two on the few dozen Ford radios I've worked on. At some point your new radio is going to fail. Guys like me won't be able to repair it because we can't get parts or service manuals, so you'll be stuck with a real high repair bill from the dealer again. As of a couple of years ago, the typical cost of removal, reinstallation, shipping two ways to one of the two remaining grossly-overpriced authorized repair centers, and their repair charge was over $450.00 for a cassette player or cd player radio. The same bill for a Chrysler or Ford radio from their authorized service center is $250.00 for a cd / cassette combo radio, plus shipping, and you can install it yourself with nothing to reprogram. Even that is three times what I charge dealers. You might want to reconsider that Tomtom or some other portable unit. From what I've heard, they work really well. You won't get the factory look but you won't be sitting in a puddle of tears if it breaks.

Ask for the details at the dealership's parts department for the radio, then at the service desk for a labor estimate. With that, you'll be better able to make an informed decision. I have a half dozen brand new Chrysler GPS radios. One model has a list price of $1595.00. The newer model goes for around $1800.00, and an older model costs $1195.00. With all manufacturers, half of the cost is for the name but a lot of research and development time went into matching the tone to each vehicle's body shape and interior design. Aftermarket radios are a "one-size-fits-none" but they often last longer than the original stuff.