The 2012 5speed Auto (A580) gear ratios are:
1st - 3.59
2nd - 2.19
3rd - 1.41
4th - 1.0
5th - 0.83
Someone asked where the chart came from. It's from Alpars.
Here's the previous auto for comparison, the 42rle:
1st - 2.84
2nd - 1.57
3rd - 1.0
4th - 0.69
Reverse - 2.21
BTW, an easy enough way to get engine rpm's at a given speed with a specific set of tires and your transmission and axle ratio, with your transmission in any given gear is to multiply out the final drive ratio in that gear, then multiply that by the tire manufacturer's specified rotations per mile. This will give you engine rpm's at 60mph. Then divide 60mph into the speed for which you want to know rpm's. Then multiply that result by rpm's @ 60mph and you will have rpm's at that speed. Since there's some rounding and other factors like tire wear and inflation, it isn't exact but it is darned close.
2012 auto with 4.10's and 35" KM2's (model #38371. 35x12.5R17/D,) in 5th/OD on the highway at 70mph.
.83 (the 5th gear ratio) X 4.10 (axle ratio) = 3.403. Round to 3.40.
3.40 = final drive ratio.
BFG's spec'd revolutions/mile = 598
598 X 3.40 = 2033.2rpm @ 60mph. Round to 2033rpm @ 60mph.
70mph/60mph = 1.166666... Round to 1.17.
1.17 X 2033 = 2358rpm @ 70mph
At 50 mph:
50mph/60mph = .83333... Round to .833.
8.33 X 2033 = 1693rpm @ 50mph