COMPATIBLE WITH GMC SIERRA 2500/3500 HD (2020-2025): Fits SLE, SLT, Denali & Elevation. This FN Tuned throttle response controller optimizes 6.6L V8 & 6.6L Duramax Diesel engines for safer merging and hauling heavy loads on the highway. UPGRADE YOUR DRIVE: Make your engine roar with 4 modes made for the street. 36 settings reduce lag for seamless traffic navigation, ensuring instant acceleration for safer highway merging and overtaking. PLUG-AND-PLAY SETUP: Install in 15 minutes without tools. The device connects directly to your Sierra 2500/3500 HD gas pedal sensor. It leaves no footprint on your ECU, ensuring a safe upgrade that keeps factory settings original. ADVANCED CONTROL: Adjust settings wirelessly with the free FN Tuned app. Safeguard your truck with subscription-based Anti-Theft, locking the pedal to prevent theft in parking garages, driveways, or daily commutes. UNLEASH POWER: This throttle controller does not write to the ECU. It removes lag for instant response. Works with aftermarket intakes and exhausts, helping you unleash the full roar of your engine during driving and heavy hauling duties on the road. Upgrade your GMC Sierra 2500/3500 HD with the FN Tuned Throttle Response Controller to instantly reduce pedal lag and improve throttle sensitivity. This device is specifically calibrated for 4th Gen (2020, 2021, 2022, 2023, 2024, 2025) models. It works with all trims (SLE, SLT, Denali, Elevation) and engines (6.6L V8, 6.6L Duramax Diesel) to transform your driving experience using four dynamic modes: Slöw, Cruise, Fast, and Send It. With 36 sensitivity settings, you can easily dial in your vehicle's response for a powerful, personalized feel. Enjoy a straightforward upgrade with Plug & Play installation that takes just 15 minutes and does not modify your vehicle's ECU or factory software. You can wirelessly control every setting via the free mobile app, which includes an optional, subscription-based Anti-Theft feature to lock the gas pedal. This fully reversible system works seamlessly alongside your other aftermarket upgrades, giving you total control without compromising your vehicle's factory integrity.