We have taken the factory Transmission controller or TCM a step up with new operating system patches and fixes that make the Trailblazer SS much more pleasurable to drive. Included in these controllers are a WOT throttle lockup patch. This locks the torque converter in second gear at WOT for better ETs and MPH. We also have a patch that keeps the torque converter locked if you lift off the gas in part throttle. The torque converter still unlocks when you press the brake. This patch has been known to greatly improve fuel mileage especially in vehicles with aftermarket stall converters. Only 2006-2007 TBSS’s supported, sorry!