Hi new to this forum and just got a quick question. I currently got a 03 gt and havent been able to do much to it at all because of money but im finally getting some and are looking into getting gears. I was looking at the 4.10 gears at AM.com but i was just reading on that you have to buy a T-lock too? whats this about and its required for a new set of gears? Thanks for your help guys.