I third the 4.10 swap. It may be unintuitive that you can get better mpg with shorter gears, but you can. Key to this is the fact that with shorter gears on inclines you can often stay in overdrive (or a higher gear) without downshifting to ascend said inclines. People told me I'd lose mpg with my 4.56's (with 34.3" tire diameter) but when I changed from 3.73's to 4.56's I gained ~1.2mpg combined (hwy/city). I saw an increase of closer to ~2mpg on the highway, largely because I don't drop out of overdrive at highway speeds unless I'm in steep hills or the mountains. On the flip side, mpg goes south really quickly if I travel more than 70mph ... which I seldom do. Food for thought.