The Hummer H3 has "Adaptive" shift learning. Even going from 32" to 33" no computer "reprogram" is necessary. I have 35" BFG MT and mine shifted funny for about 3 days and then bang "Adapted" Talk to your H3 Mechanic he should be able to verify this. Hummer engineering has also commented on this in a few earlier articles during the "promotional phase of the H3" Hope this helps.
BTW here are the stats for the 35" Change from the 33'S"