Because unpredictable length of time needed to gain access to the ECM for the 2017+ vehicles, we are not able to tune them in person. We would tune your vehicle via our AutoCal, that will allow us to see your vehicle data, and provide your custom tune files via email. The AutoCal is the same quality tune as the in person tune. You can also use it to go back to factory settings, and if you add mods, or make any changes, you will be able to receive free tune updates via email as long as you own the vehicle.What if you have a 2018 Tahoe 5.3??? It says only 1998-2016. Thanks, Keith