I plan on running 39.5" tires. Ok it says that if I run 4.56's with my sm465 and a 39" tire I will be at 2554rpm at 65mph. If I run 5.13's w/39" tires I will be at 2873rpm at 65mph. At 75mph I will only be running 3315rpm. This seems a little off to me. I had thought that with 5.13's I wouldn't be able to hit the highways but 2900rpm doesn't seem all that bad. /forums/images/graemlins/dunno.gif I dunno does this seem right to you guys? I drive 99% of the time around town and off-road, the only time I would ever hit the highways would be when I go to BB04, BB05, BB06,... and maybe the odd trip to wheel on the coast or something. If it is then I would much rather go with the 5.13's /forums/images/graemlins/thumb.gif My final crawl ratio would be 65.76 which would be great for the trails around here. It should also help me develop wheel spin a little quicker too right?