70 mph is 2400rpm. Speedo is corrected by procal; 6 gear on the manuals is 0.02 difference with new 5 speed. Barely noticable. My buddy has a 2012 2door with 4.56 6 speed 35's mine 2012 4 door 4.10's (factory). His will roast the 35's. He went from 3.21's so def improvement for cost. Spend the money on a cool summer top and other gadgets if your going to go 4.10. 4.88's will be too high rpms on freeway. If you really want to regear go 4.56.
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