hello i do not match the parameters of your question but may i provide my experience. my rubicon came engineered from the factory with 33" tires and 4.10 gears. i went with a 4.5" lift, 40" tires and 4.88 gears. now before anyone gets their panties in a twist, look at the ratio between original tire size and gear ratio. 33/4.10 = 40/to what? 4.97. i've yet to find a 4.97. i could go with 5.13, more grunt or 4.88, lower cruising rpm. i've put 27,000 miles on the modification as it is our daily driver. the bride and i sold our second unused vehicle after we retired. i never wished for 5.13 or 5.37 last summer at SMORR, Hot Springs Park, Ouray CO or Moab. i believe there would be an advantage to other gears but i wasn't running the baja 1000. the bulk of my driving is interstate. although i will deny it in a court of law, i set the cruise at 79 in a 70. yes the speedo was recalibrated and is occasionally checked via gps. according to the jeep's mpg readout i'm at 15.5 mpg average, city highway. i would estimate at a minimum i added 500 pounds of post factory weight. if memory serves correctly, i averaged 18 mpg stock. yes, i decreased the mpg by 14% but definitely increased the FUN FACTOR 1000%. so my question to you sir is, what is more important to you and you alone: saving $ on gas or having a blast? and yes, even at 64, the cool factor still plays a hand in my jeep's appearence!
