I have the pedal commander and even that states you should remove it before dropping it off at the dealer. Its a guarantee that if you get a code on ur truck that relates to performance of the truck. The dealer will see you have a tuner. With that said they still have to prove that the tuner is directly related to the failure or issues to not warranty the problem. Don't fool yourselves into thinking they would never know. With all that said. I bought my 07 stang brand new. After the first 6 Months I had it tuned. Once i caught the bug of modding. It didn't stop. I didnt care about the warranty. I had it supercharged, cammed, geared, with many other mods. So clearly I know the love of better performance. My car now lays down 540Torque and runs 10.9 in the 1/4. Still street worthy.