Here is a great gearing calulator :
http://www.grimmjeeper.com/gears.htmlplug in your info and play with the numbers to get it where you want it to be.
What size tires are you running ??
What year transmission ?
Here is also another calulator for gearing info :
http://www.lepayne.com/gears.htmlThe numbers don't add up but it is late and maybe I am just not reading correctly.....
If the previous owner followed the Trail Tough article, the R&P gearing of 4.57 would be for running 32" tires.
With 32" tires, 4.57 R&P, & 4.16 t-case (with a late transmission) you would be turning around 3628rpm at 55 mph with crawl ratio of 69:1.
Now if the previous owner wanted to run a 32" tire and geared the ring & pinion for such BUT left the stock 26" tires on it, then they did NOT follow the tech article and that is why you are turning 4500rpm at 55mph.
From the Trail Tough article : ..
..reduce the ratio at the ring and pinions relative to the size tire you want to run, then select the transfer case gears that will best meet your 4-wheeling needs.