I’ve decided and purchased 22.5 conversion for my c4500 2wd and I plan to install them as soon as I can have a break from work. 8x275mm lug 22.5 Alcoa’s on dynatrac 255/70r22.5 ma400 mixed tires.
I was thinking of going with the same tires and size. How do you like them so far. More importantly, I want to know how much of an RPM drop at the same speeds before the new Stires and after, you got going with these tires that measure roughly - 37". I have a 4x4 with 5:13s and an trying to decide what tire size to go with (it'll fit 40") to reduce my engine rpm at highway speeds. With the small stock 33" tires I'm running at 2400 rpm at 65-70 mph @7.5-8 mpg and around 2100 rpm at 55-60 @9-9.5 mpg.