right, that is good for him to know. i've just always heard over an inch diff messed up the abs.
but they do make 20" tires that match up with 22" tires in height you just need skinny ass tires on the 22s...rim size usually has nothing to do with it.
you coulda run this
255/40/20 = 28"
255/30/22 = 28" or (stretch i know, but still) 315/25/22 = 28.2"
255/35/20 which is 27"
295/25/22 which is 27.8" and still be good.
no abs problems guaranteed. but this thread is about same size rims so none of this matters anyway.