im getting 1793 RPM's @ 85mph with 235/85/16's and 3.55 gearing in double over.
are you sure your at 1850 rpm now at 85? or do you have something other than stock tires?
Right now its a set of #.55 gears and in double overdrive at 85 mph I'm turning around 1850 rpm... I would like to change that to 2000 or 2100 rpm....
if your running stock tires then im getting exactly what your after with a set of 4.10's;
2070 RPM @ 85 MPH in double over.
edit,
i just saw your recent thread.this could change things again.
if you plan on swapping to a dually.do you plan on running stock shorter 215/75/16's?
........
looks like id have myself a set of 5.13's with my short 225/75/16's if i had a GV.
id be cruising around in double over @ 45 MPH in the idi's peak torque range (around 1400+) and hitting the max fuel economy.
shoot,id go right to a set of 5.38's if i could find 'em.
ya don't wanna sell that do ya?