2014 5.3 Tire size

[NoLimitAutomotiveTuning]

Is there a way to calibrate the tire size on a 2014 5.3L chevy 1500?

[GMPX]

I thought these days most of the speedo cal was in the ABS which broadcasts the speed over the CAN bus (I might be wrong).

[NoLimitAutomotiveTuning]

I'm not 100% sure how they do it now, I do have a customer he had bought his truck from the dealer and they used a Hypertech Speedo Calibrater on it and set for a 35" tire but he has now gone down to a 33" tire and we tuned it but cant get the speedo accurate like it was with the 35's

[Taz]

The three main Speedometer parameters are: H0102, H0122, and H0105. H0102 and H0122 should not have been altered for a tire size change (35 inch) - so these should still be the stock parameters. Adjust H0105 as necessary for the new tires (33 inch).

[NoLimitAutomotiveTuning]

I will give that a try, Thank you!!