235x75x15 on the stock wheels is as big as I would go without a lift. You might be able to squeeze in 30s if you stay with the stock wheels. You might loose a little MPGs with the 235s but not much.
Dennis


95 Sportage, gone but not forgotten.
98 Jeep TJ, 4" Zone springs with RC Long arms, Ford 8.8", 4.56 gears & Detroit locker rear, D30, 4.56 & Detroit Trutrack front.