Can't change tire size after 1r13 update

[be2real]

So, I did the update and the calibration update as well but after doing so I cannot change the tire size anymore. I'm using the 91 octane tune and I did the mod before I installed it but kept getting an error message saying that the device could not read the VIN PCM and to make sure the truck was on the on position (which it was the whole time). I went ahead and installed it anyway without adjusting the tire size but I would like to go back and do so in order to make sure my speedo is reading the speed correctly. Can one of the techs please advise?

Thanks

[BlackOverlandHemi]

As far as I know they still have the tire size adjustment all f*ed up. I have a 12 Grand Cherokee and changed my tire size before looking at the forums. I ended up with a ABS light that could NOT be cleared. Cost me $160 to have the abs fixed and they didn't even respond to refunding or even apologizing for my trouble. I only have their tuner because of the hemifever tune, and I hate even turning the thing on with all the bugs. For now my radar detector and on trips my garmin as backup to my jeeps gps, both read my mph so I just glance at them to check my speed. Really sucks they can't fix the problem and still advertise that it can adjust tire sizes. With the abs light on it does mean you have no abs so be ready to if you have never drove without it.