The Power Pup Downloader for the 2001-2006 Duramax LB7, LLY, and LBZ is best downloader in the market hands down or should we say paws down. No other downloader in the market offers more features.
The Power Pup has power programs of 50, 70 and 95 horsepower, with the ability for the serious off-road driver to upgrade to 150 additional horsepower. The upgrade to the 150 HP power program is for off-road use only. To activate the 150 HP power program follow this link:   Unleash the Power
The Power Pup also gives the driver the ability to remove the speed limiter on the 2002 and 2003 Duramax, and the ability to adjust the speedo for different tire sizes. Finally, the downloader also contains OBD2 functions to scan and erase engine codes.