Fits 2020-2023 6.6 L8T GM Silverado/Sierra

Part Number: 8266-R

The 2020-2023 6.6 L8T GM gas trucks have been locked down since their introduction. Owners of these trucks have been waiting patiently for a tuning solution, and DiabloSport has delivered in a big way! The new 8266-R kit includes our inTune 3 handheld tuner, along with our industry exclusive locksmith device and harnesses required to unlock the ECM in your truck. Once unlocked, the inTune 3 offers up tunes for 87, 91 and 93 octane fuels, as well as 2 transmission tunes to choose from. Beyond the preloaded tunes, we offer a host of user adjustable parameters, like throttle response, speed limit, tire size, and more. We've even added some new features for drivers of these newer trucks, like the ability to recall your last mode setting!Get power you can feel, with DiabloSport!

Features and Benefits

• 2020-2023 Silverado 2500/3500 6.6 L8T
• 2020-2023 Sierra 2500/3500 6.6 L8T
• 28 rwhp over stock on premium fuel
• 50 rwtq over stock on premium fuel
• Tunes for 87 octane, and premium fuel provided
• ECM unlock included!
• Unlock and Tune, at home!
• Preloaded tunes for multiple octane levels
• Support for 6.6L L8T applications with 6 speed Transmission
• Throttle Boost setting for adjustable throttle feel
• Adjust speedometer for larger tires (26"-38")
• Calibrate speedometer for gear change (3.42-5.13)
• Remove speed limiter for increased top speed
• Adjust engine rev limiter for increased RPM range (+/- 400 RPM)
• Adjust engine idle speed in Park/Neutral and Drive
• ‘Keep Drive Mode Setting’ allows you to select a drive mode and it will remember that mode next time you start the truck!
• Adjust fueling at WOT in multiple RPM ranges
• Calibrate spark timing at WOT across multiple RPM ranges
• Front/Rear TPMS threshold adjustment
• Air Filter Monitor system control
• Transmissions adaptive relearn