Well I do not know why I would need to change gears, The tires are very close to the same size as the corresponding turf tire is. I do not lock in the 4WD unit unless I am in soft / slippery ground and actually need it. And so even if it was not a perfect match there would be enough slip in the contact with the surface to relive any pressure. Remember no matter how well you have sized your tires there is no such thing as a perfect match Wear / under or over inflation of the tires and other unknown factors make a perfect match impossible anyway. I used to be a member of a 4 wheel drive group many many years ago, and this subject would come up, Despite seeing guys run with almost flat tires, slightly mismatched sets and other problems we never had anyone do any damage to the rigs that could be contributed to this /forums/images/graemlins/smirk.gif