Dave -Be aware that the HD truck tire industry is rapidly changing to metric sizing, like we've had on our cars for a dozen years or more. So it's a little more involved than just walking into a store and sayin' "Put tires on my bus."
One thing to take into consideration is "tire revs per mile." The stock size for your MCI was 12.00R22.5, and that's what MCI designed the powertrain around. Thus to keep stock performance, you want to run tires that approximate the same RPM as the OEM tire. This will mean a little homework on your part, to find the average revs per mile for 12R22.5s among the various manufacturers. That will then become your baseline to work off of.
More RPM = lower top speed and greater fuel consumption.
Lower RPM has the opposite effect.
Then start comparing the "old" sizing nomenclature with the new metric sizing to find something equivalent or suitable. Once you've decided, then start shopping price.
Make sense?
FWIW & HTH. . .
