Bought my jk used with a lift etc. Is there anyway to identify my gear ratio? I'm wondering because my mileage is horrible. I get like 12 mpg in town.

 

Try a build sheet. It's free

 

It was used. No idea what the previous owner did. Hence the question.

 

Jack up the rear end. Count driveshaft revolutions while rotating the tire. Turn the tire 2 complete rotations if your other tire remains stationary and does not rotate. Turn the tire 1 complete rotation if the other tire turns in the same direction. The number of times the driveshaft rotates equals the gear ratio. If the driveshaft rotates about 3x, the gear ratio is 3.07. If it rotates 3 3/4 turns, the gear ratio is 3.73. You can mark the driveshaft to help you count.

Almost certain you spin tire twice, as other tire doesn't spin. My axle only turned about 3 1/4 times... Damn 3.21's!

Hope this helps.

 

here is the video to calculate gear ratio.. hope it works for ya..

http://www.youtube.com/watch?v=i_Eny...feature=topics