need info for my truck

i have a 2000 mercury mountaineer whats the largest size rim i can fit on it w/o modifications? will 22's fit the vehicle? also, what is involved with keeping spinners clean and smooth spinning?

Due to all of the problems Ford is having with those vehicles and the Explorers, I would stick with the stock sizes. The vehicles are top-heavy enought without putting a wider, lower profile tire on them. That will make them even more unstable. It's just not safe. Tire Rack stopped selling plus size fitments on these vehicles even before the offical tire recall started.