OK, to you folks with the 5.2L running 4.11 gears... how many RPM's are you seeing with O/D on going 70 MPH on the highway?

Thanks.

 

With stock tires you should see about a 300 rpm increase at 70mph compared to 3.55's. It doesn't make a difference what engine you're running as it does final drive ratio, which factors in road speed, tire size, transmission ratio, transfer case ratio, and axle ratio. Here's a calculator you can plug some numbers into: http://www.4lo.com/4LoCalc.htm

 

running with 265/75 r /16 coppers rpm at 70mph around 1800... at 50mph 1100 rpm ..I watch this real close and my mpg.. worse mpg 14.5 , best 19 ...