Take your 6.6L Duramax LB7's power to the next level with our excellent selection of aftermarket Chips, modules and tuners! Gain additional horsepower, torque and throttle by upgrading your stock PCM to a performance-oriented tuner! Engineered to overhaul your truck's shifting for an enhanced gear-holding and optimized shift pressures, GM 2500HD/3500HD owners can expect an excellent increase in their truck's performance. Achieve improved injection timing/pulse and fuel rail pressure with a new aftermarket PCM Tuner from Alligator Performance. Pair your new tuner with our excellent selection of Exhaust Upgrades andFuel Upgrades! GM Duramax Fitments: 2001, 2002, 2003, 2004 GM 6.6L Duramax.Submodel Fitments: WT, Custom, LT, LTZ, High Country, 1LT, 2LT, Pro, SLE, SLT, AT4, Denali.Some exceptions apply, please see individual product pages for specific fitments.