[Jackpine]

ballistmike - sorry to get in on this so late, but I've been away.

If you change tire sizes during the year, I would NOT get specific tunes for each tire size. Just get tunes for the kind of driving you do, like "towing", "highway", "around town", whatever; and, tell Bill the tire size you have on the truck throughout MOST of the year (which I suspect is your "summer" tires). Then, he'll put that tire size into your tunes and you won't have to adjust anything.

In the winter, when you change tires, it's a simple matter to go into the "Custom Options" menu and change the tire size. Then when you remount your summer tires, simply reload your tune without any custom options - your tire size will be correct again.

And, as Lars was telling you, as long as the TS and GR are correct when you tell the Gryphon to program the PCM, the shifts will happen when they're supposed to, no special tune is needed.

- Jack