rear gear id swap

[j1mmy]

i have a 94.5 crewcab 2wd drw powerstroke with a 5 speed... the only hauling i do, is towing a 8k pound 27' boat 30 miles highway a few times a year. im wondering if the rear gearing has been changed or if i could/should swap to a higher rear gear.. rite now i get to second/almost third gear in my driveway. i go into 5th/OD below 40mph.. at 65mph i am at 2500rpm. much over 70 and i would be red lining..
i drove semis so i know about diesel trucks,but this is my first diesel pickup..it really doesn't seem normal to me. does it sound like the truck has been regeared way too low? should i go to a higher gear to make it more drivable? i think 4:10 is stock, i can get a good used 3:55 ring and pinion set for $30..

[baderic03]

U got more then a 4.10 gear in that truck if it was a 4.10 with stock 235/85-16 at 65mph u should be at like 2100 It sounds like u got 4.88s or 5.13s

[backwoodsboy]

Sounds like 4.88 if you're red lining at 70.
For $30 get the 3.55. My truck will do 70mph at <1900rpm. This is with 35" tires, so we're probably looking at more like 75mph.

[351fifty]

find yourself a 4.10 geeared axle, it will have alot better highway etiquite than what your running now, i have 4.10's and i doont redline till past 85 (thats where mine stops counting but keeps going)

[j1mmy]

thanks for the info..i think i am going to get the 3:55 gears and try it out.. rite now i cant do anything but idle in 1st or 2nd. i hit 4th before 20mph. and i am only getting 14mpg. it feels like im driving with a transfer case in low gear but my truck is 2wd.. does anyone know where i can get a book or info on setting up a rear end. i know the basics but have never actually done it in person..

[terryknight]

find a shop it needs to be fairly precise. And there is info all over the web, some good some not so good

[madpogue]

If you're really curious - put a chalk/paint mark on the driveshaft, jack up the back and spin one of the wheels one revolution. Count the number of turns of the driveshaft based on the mark. That's your ratio.