Tire Question...12R22.5

[John]

I have started looking for new tires for our coach as it has the
origional tires on it. While they are showing no cracking at all, I am
still concerned about their age and would like to start swapping them
out before I have to do it from the side of the road. The current
tires are 12R22.5 which seems to be a lot more uncommon than
11R22.5s(which I run on my dump truck). From talking to a couple tire
people they say the 11R22.5 are a little smaller(shorter). Has anyone
switched from the 12s to the 11s? Any recomendations on a particular
brand?

Thanks,
John Cassel
98 Wanderlodge LX