Our custom Heavy Tow tune is the safest way for those who tow big, tow heavy, or tow a lot. What’s heavy? Over 8,000 lbs and up to your truck’s 2017, 2018, 2019 Chevy Silverado or GMC Sierra GVWR (Gross Vehicle Weight Rating). Our fine tuned calibrations expertly optimize for power, torque, smoke and vehicle reliability. ECM & TCM Tuners, Hardware and Credits are included.