With an 8.8 I finally have the ultimate choice in gears. I have 3.55 in the one that I recently purchase but am seriously contemplating buying some 3.73’s maybe even some 3.92’s. I think the 3.55 is a good gear and while cruising I think I only saw about 200 rpm difference cruising at 80 rpms. I think I read the difference between the 3.73 and 3.92 is about 150 rpms at about 80 mph. So it seem that all three gears are fairly close to one another. Last season I ran a 29” tall tire and ran 3.73’s from my getrag and had great success I think the overall effective gear ratio was like 3.55 with 29” tall rubber. I have since decided to go back to a 28” tall tire. With ford racing and summit gears for the 8.8 all being under 200 buck and the fact that I have to put a LSD in the car makes me want to make a gear swap at the time if I plan on doing it to save on the labor. The only thing is I want to make the best choice. I am thinking going back to 3.73’s but I have the itch for 3.92’s. I only drive my car on the interstate at most 3 hours from home. I really don’t think gas mileage is a factor but more am concerned about track performance. I have gotten some good feedback from another member on here but wanted to see what others thought as well