Speedometer recalibration

[Sour_Squirrel]

My 2017 GMC Sierra is now riding on 35” tires.    Is there a calibrator that will make my speedometer read the correct speed?

However I don’t want to add a tuner or to change the factory computer settings. 

I thought I read somewhere that there’s a calibrator that plugs into the OBD port and doesn’t leave any trace of ever being there if I unplug it from the OBD port. 

[wforrest08]

http://www.hypertech-inc.com/SpeedometerCalibrator.aspx

 

This is what my stealership uses on the trucks they level/lift only corrects the speedo. I’m sure it will show on the flash counter in the ECM which is why I had them do it so if there is a warranty issue down the road.