In fear of being flamed: I have searched... and not found what I am looking for.
I have 31" tires on my 3.07 gears. I really do not like the drop in power I have experienced from factory, and I really would like to get back to a more factory-like power level. My math (linear scaling is around 3.4 which just doesn't exist) puts me at looking into 3.55 gears, but I had a conversation with a tech with Just Differentials, who recommended 3.73's or 4.10's which in 5th at 75 would put me outside the 2100-2300 RPM equilibrium I heard the 4.0 lokes to have on the highway. I don't think he took into consideration the .79 5th gear in the AX15, and figured I had AW4 like ratios. I have done some reading and searching, but nobody really seems to have documented what I am looking for. I am not changing tire sizes anytime soon, this is my DD/hunting jeep, and most people regear at 31" in anticipation of larger tires it seems. Is my mileage going to be that much worse at 3.73 vs 3.55? Has anyone on here done 3.55s and an AX15 with 31" tires?
31 inch tires at 75 MPH
RPMS Gears
2279.8 3.55
2395.4 3.73
2633 4.10
I have 31" tires on my 3.07 gears. I really do not like the drop in power I have experienced from factory, and I really would like to get back to a more factory-like power level. My math (linear scaling is around 3.4 which just doesn't exist) puts me at looking into 3.55 gears, but I had a conversation with a tech with Just Differentials, who recommended 3.73's or 4.10's which in 5th at 75 would put me outside the 2100-2300 RPM equilibrium I heard the 4.0 lokes to have on the highway. I don't think he took into consideration the .79 5th gear in the AX15, and figured I had AW4 like ratios. I have done some reading and searching, but nobody really seems to have documented what I am looking for. I am not changing tire sizes anytime soon, this is my DD/hunting jeep, and most people regear at 31" in anticipation of larger tires it seems. Is my mileage going to be that much worse at 3.73 vs 3.55? Has anyone on here done 3.55s and an AX15 with 31" tires?
31 inch tires at 75 MPH
RPMS Gears
2279.8 3.55
2395.4 3.73
2633 4.10