Heres the thing about the word "void" when referring to warranty. Nothing you can do to your car will ever officially "void" your warranty. And say for example if you change the rear brakes to disc, then the fuel pump goes out, the pump will still be covered under warranty unless they can prove you changing the brakes was the cause, and is illegal for them not to cover it without said proof under the magnasson moss warranty act of 1975.