I was told by my dealer that the superchip would void the warrantee on my 05 6.0 diesel drive train. Is this true?

 

It has the potential to void the warranty. The mere fact of putting one on your truck doesn't in of itself void the warranty, however, if they are aware that you have one on there and you come up with some type of drivetrain warranty claim, they could make a stink of it and more likely then not they will win rather or not the tuner was the cause or not.

On another note, I wouldn't use a superchip on a 6.0. Get something that you can get custom tunes for, your engine and tranny will appreciate that much more then the superchips.