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Fitment

YearMakeModelSub Model
2020-2023GMCSierra 3500 HDAT4
2020-2023GMCSierra 2500 HDAT4
2020-2023ChevroletSilverado 3500 HDWT
2020-2023GMCSierra 2500 HDSLT
2020-2023GMCSierra 3500 HDSLT
2020-2023GMCSierra 2500 HDSLE
2020-2023GMCSierra 3500 HDSLE
2020-2023ChevroletSilverado 2500 HDLTZ
2020-2023ChevroletSilverado 3500 HDLTZ
2020-2023ChevroletSilverado 2500 HDLT
2020-2023ChevroletSilverado 3500 HDLT
2020-2023ChevroletSilverado 3500 HDHigh Country
2020-2023ChevroletSilverado 2500 HDHigh Country
2020-2023GMCSierra 3500 HDDenali
2020-2023GMCSierra 2500 HDDenali
2020-2023ChevroletSilverado 2500 HDCustom
2020-2021GMCSierra 3500 HD
2020-2021GMCSierra 2500 HD
2020-2023ChevroletSilverado 3500 HD
2020-2023ChevroletSilverado 2500 HDWT
2022-2023GMCSierra 3500 HDPro
2022-2023GMCSierra 2500 HDPro

Quick Specs

  • Country of Origin: US
  • Sold As: Kit
  • Availability: Available
  • Universal: No
  • Cylinders: 8
  • Harmonized Tariff Code: 8512204040
  • Part Number : 8266-R

Important Notes

ATTENTION STATE OF CALIFORNIA CONSUMERS

WARNING: Cancer and reproductive harm –

inTune 3 for 2020-2023 6.6 L8T Unlock and Tune Kit Unlock and Tune your 2020-2023 6.6L L8T powered Silverado or Sierra, in your driveway with inTune 3! DiabloSport

Fits 2020-2023 GMC Sierra 3500 HD AT4 2500 Chevrolet Silverado WT SLT SLE LTZ LT High Country Denali Custom 2020-2021 2022-2023 Pro
4.9257075471698 848 5
98.514150943396%
4.9/5 out of 848 Company Reviews. Rating:
inTune 3 for 2020-2023 6.6 L8T Unlock and Tune Kit Unlock and Tune your 2020-2023 6.6L L8T powered Silverado or Sierra, in your driveway with inTune 3! DiabloSport
799.95In stock
Fits 2020-2023 GMC Sierra 3500 HD AT4 2500 Chevrolet Silverado WT SLT SLE LTZ LT High Country Denali Custom 2020-2021 2022-2023 Pro
  • Brand : DiabloSport
  • SKU : 8266-R-CLNS
  • Part Number : 8266-R
$799.95

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Product Details

The Diablo Sport in Tune i3 8266-R Kit is the breakthrough tuning solution for 2020-2023 GM trucks equipped with the 6.6L L8T gas engine These trucks shipped with locked PCMs that blocked tuning-until now.

This complete kit includes the powerful in Tune i3 handheld tuner, along with Diablo Sport's exclusive locksmith device and harnesses required to unlock your ECM.

Once unlocked, the in Tune i3 unleashes dyno-tested tunes for 87, 91, and 93 octane fuels, delivering gains of up to 28 rear-wheel horsepower and 50 rear-wheel torque over stock

Alongside raw power, the tunes refine drivability with better throttle response, improved part-throttle performance, and smoother shifting, transforming how your truck feels on the road or under load

Beyond the preloaded calibrations, the i3 also provides a wide range of user-adjustable parameters, including tire size adjustments, speed limiter removal, throttle sensitivity, and more

Added features for these newer GM platforms include last mode recall, so your truck always remembers your preferred driving settings

For GM truck owners ready for a true performance upgrade, the in Tune i3 8266-R Kit delivers proven horsepower and torque gains with the drivability improvements your 6.6L L8T deserves

  • 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 Inch)
  • 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
  • РІР‚пїЅKeep 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

Details:

  • Fuel Type: Gas
  • CARB (California) Compliant: No
  • Body Material: ABS
  • 5 Volt Data Logging Inputs: Yes
  • 50 State Legal: No
  • AC Adapter: No
  • Accepts Custom Tunes From CMR: Yes
  • Case Included: No
  • Color Touch Screen Display: Yes
  • Custom Tuning: Yes
  • Data Logging: Yes
  • Emission Code: 7
  • Erases Fault Code: Yes
  • Grade Type: Performance Regular
  • Instruction Manual Included: Yes
  • Performance Tunes: Yes
  • Personal Computer and Mac Compatible: Yes
  • Product Type: Handheld Tuner
  • Software Included: Yes
  • Speedometer: Yes
  • Sub Category: Engine Service
  • Systems Covered: Transmission Engine
  • Upgradable: Yes
  • Wi-Fi Updates: Yes
OUT OF STOCK SHIPS FREE

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