Quote:
Originally Posted by mbozz282
It has 18 speed with 335 rears and 22.5 tires .I pull refer. loads from 55000 to 80000 mostly east of miss. river .My idle time was around 31% and i drive alittle fast i know between 68 and 72 mph around 1400 +1475 rpms.
You got an almost perfect specs, for the job you do. Try not to go over 1400, preferably 1350, cut down on idling a little, and you might be very surprise. I mean after you'll figure out, what's wrong with it.