If i were to do one and i might again one day. I would do the 770r4 with a 208 for gas mileage or a nv3550 with a 208 or 241. The step sides are a lot lighter than the fleet side trucks. You can run 33's with no lift but stay as skinny as you want to save on gas. An all terrian will get better gas than a mud terrian of the same size. Higher gears do not always get you better mileage. You to be in your torque curve during normal driving gets you the best mpg. Trim your inner and outer fenders to save wieght. I welded in c channel with a reciever hitch to do away with the rear bumper. I tastefully trimmed the front so that if i backed up the front would not catch limbs or branches. Get rid of the dash and bend a piece of plastic or sheet aluminium to go in its place. Aluminium wheels and 35's my truck was under 2400 running a 350 with a 3 on the tree and a 205 case. Ask around a gear ratio of 3.73 or 4.10 might get better mpg around town if running 33's you might be surprised. You said something about short trips so even with stock tires i would not run lower than 3.08 gears. Good luck on your truck. If want to keep it cheap and get down to 2000 lbs go with a good 4.3 liter. If your wieght does not get down though it will cost you more in gas.
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