Not sure which 2003 Chevy Silverado Performance Chips & Programmers are right for you? We have over 3535 customer reviews, with an average rating of 4.5, to help you find exactly what you're looking for. Here's what some of our customers have said:
"I bought the Flash Paq tuner based on the positive reviews and the fact that it is an upgradable device. I received the item promptly from AutoAnything...thanks! Previous modifications to my 2007 Tahoe include rear drop coils and cold air intake. Also has OEM 20's and is lubricated with Amsoil products. I was looking for a little more power off the line, so I decided to try a programer. Installing the programer was easy and the whole process took about 15 minutes. There are different level settings, and I choose the 87 octane. I immediately noticed a change in the shifting through the lower gears. It was quick and smooth, shifting naturally during acceleration. My only concern was that for the first 30 miles, I heard some pinging of the valves. Not a comforting noise, but it has ceased, so I figure the on-board computer self-adjusted the timing (I plan on contacting Superchips to see if the pinging is common). I have not had it long enough to comment on the fuel milage. All in all, a great tuner if you're looking for better transmission shifting. If your expecting noticable horsepower changes, sorry my friend, you won't notice it on a 2007 Tahoe without more modifications. Still worth the money!" —Michael L from Cincinnati, OH bought a Superchips Flashpaq Tuner for a 2003 Chevy Silverado.