I'm getting ready to buy new tires for my 03 F-250 4x2. (XLT, sports package, tow package, camper springs) It has 265/75R16E tires stock. I want to put 285/75R16E tires on it. I've heard about problems with fender rubbing. With the camper springs it sits a little higher than a stock truck without them. Will the 285's fit without interferance?

I've heard from guys at a tire place that is the biggest size you can put on a stock F-250 so you shouldn't have a problem.

Yep, you'll have plenty of room. Put that same size tire on mine and no problems. Just be sure to get the speedo recalc'ed. It will be off by 2-3 mph. Cost me about thirty bucks at Ford Dealer to have done.