Re: 2002 expedition ?
You'll probably have to trim a bit, but depending on the wheel offset you could squeeze in 34" tires with a 3.5" lift. Just don't go wider than 11" or you'll have major rubbing problems at full steering lock - again, this depends on the wheels. In some cases, again, depending on the wheels, you might get away with a 35" tire, but frankly, I'd stick with a 33" for best sizing options. This way, you won't lose much performance utilizing the stock axle ratio.
'11 Ram Quad Cab 4x4 SXT 5.7L HEMI (stock); 48,500m
'06 Pontiac G6 GT 3.5L 220hp; 64,000m
'12 Chrysler 200 Limited 3.6L 283hp; 28,000m
'99 Taurus 3.0L 2V Vulcan 145hp; 154,300m - Traded
Amsoil in all vehicles!