Quote: Spend some time sorting the gear ratio too with a .50 6th. your combination with 4.10's would be only turning 1700rpm in 6th at 70mph which might be too low depending on how your engine is setup. There is a free tremec app for phones that does the calculations for you.
I have a 2010 Challenfer SRT8 with the same engine, Trans, tire diameter, and 3.91 gears. It does not like to drive 70-75. I have to drive faster then 80 to get rid of an annoying drone. I think the 4.10 will be perfect but I will run it through a calculator.
I had an 09 with the same observations, 6th is a pretty useless gear
