Originally Posted by WY-JK10

Thanks again. Finally found the gear-rpm charts in the Modified Tech FAQ. It was hiding in plain sight. Feel kinda dumb for it taking me so long. Anyway am surprised the 2400 you reported does not match the chart. With the 3.8 in my 2010 I get exactly what the chart says I should with 410 gears & auto trans with stock Rubi tires, 2080 rpm at 70 mph. The chart for the 3.6 says 2533 with same set up, so hope your number is the more accurate. Would be good to hear from others on this. From the chart layout it appears a true 2400 would be the sweet spot for my use just as I had thought before viewing it. 2400 to 2600 is all close enough to make the 410 the preferred gear ratio for me. It works well for my altitude use now & if I get the urge to go bigger tires in the future will still be great. Love my 2010 Rubi & I'm retired & on a slim budget, but I think this change is well worth the money. Hope to keep the 2012 the rest of my life & think this motor & trans combo is much more likely to hold up the 20 or so years I hope to have left than my 2010.