Back to the tire size question... Over the years, I have run 235, 255, and 245 series tires on the factory 16" wheels with a 3.73 gear.
All fit with just a tad of rubbing when turning hard (no lift) when they hit the inner fender liner and that is no big deal.
Biggest problem running the largest set of tires was the overdrive issue. It was hunting and going in and out of lock up and overdrive at 55 miles per hour CONSTANTLY and really started to drive me crazy, not to mention the fuel mileage issues from always being between shifts.
I went down to the 245 tire which still fills out the wheel well nicely and gives just a bit of extra tire lift and it works our well for shifting, etc. I've now run 2 sets of tires in the 245 X 16 size and like them. Currently running Firestone Destination AT at 245X70X16. Firestone made a believer out of me with these tires -- formerly I would have used Firestone tires to burn a brush pile, never for my daily driver -- but these new ones really perform well in almost all categories that one might care to measure!