Here is what I am thinking. Only dropping a few ratios' will not help me any.?. There again I really have no idea about which one to drop to. My truck sweet spot is the 1900 rpm range. It gets about 15mpg at that point. The problem with that is... this is about 57 mph. People blow the horn at you driving that fast/slow.
and yes this is a Hwy only truck. I do need the heavy frame. Ever once and awhile I need to carry heavy cargo. Plus the 8 foot bed is a must.
Do any of you have any experiance with the diff's from, www.justdifferentials.com
Are these quality ring and pinions?