When I was putting in a set of 4.10s I learned the old gears were 2.41. That was a freeway flyer and I couldnt even use 5th gear. I wouldnt recomend going that low, it defeates the point of running a 5 speed. Now with the 4.10s I find that I am cruising around town in 4th and driving on the freeway in 5th going about 65mph at about between 2500-3000rpm. I used the id decoder on the 5speed site, and it said My tranny was a .68 5th gear.