The T1XX platform made its way to GM's HD series trucks for the 2020 model year. With it came major upgrades inside, outside, and most importantly, under the hood. The base engine became a 6.6L LT-based V8 producing 401 horsepower. The 6.6L L5P Duramax is the line-topping diesel and provides 910 lb/ft of torque in stock form. No matter how you put your HD truck to use, we have the parts to make it perform better.

Holley’s lineup of tuner accessories includes cables, mounts, and expansion systems for DiabloSport, Superchips, Edge, and Dinan devices. Keep your tuner connected, secure, and ready for performance adjustments.