Help with ideas for tow/work vehicle

[Toe_cutter]

My current vehicle is an early 90's Chevy 3/4 ton, it pulls double duty as a work vehicle and daily driver. Purchased it the first of the year and averaged 15 mpg. After a few mods and adjustments its average is roughly 20mpg combined, towing/unloaded, city and hwy over the last 6000 miles. So far I've got a warm air intake, plugs, wires, cap and rotor, advanced timing to 4* btc, new injectors and increased fuel pressure, heated 02 sensor, and 3.73 gears and a 4l80E trans. I also have an underdrive pulley set ordered, and 2 small electric fans are on the way also. I'm looking for any tips or ideas on how to try and milk a few more mpg out of the truck, also some creative ideas on changing up my gearing for better economy but still keeping pulling power.

[Toe_cutter]

For gearing I was thinking about finding a divorced transfer case and bolting it in behind the transmission and swap the rear end to the highest gears I can find, to allow a low range for towing while keeping a good cruise rpm. Or maybe finding a newer model 6speed auto from a wrecked donor and trying to make that work. Any thoughts

[oil pan 4]

Electric fans are a good idea.
Going to synthetic 5w-40 Vs. regular 10w-anything has been shown to give about a 3% boost.
The Th400 trans and the 3.73 gears are holding you back big time. You could live with the 3.73 gears and get good milage but it would require a transmission swap.

[kir_kenix]

A manual trans swap is probably the biggest gainer I can think of without losing the ability to tow. You can always do the other little things like synthetic fluids all around, grill blocks, tire pressure bump, etc to get a little more out of her.

[WVengr]

If you want to drop alot of money you could get a gearvendors overdrive unit and install it, would help with milage plus give you gear splitting to make towing easier, but those are really expensive. Maybe you could find a used one somewhere...

[ConnClark]

If this is a diesel a warm air intake is counter productive. It will hurt power and economy as well as increase pollution (NOX). There are plenty of discussions on this. Your best bet is a cold air intake with some form of ram air induction.

[oil pan 4]

Ram air was the first mod I did to my diesel and over all was the best single mod I did.

[mnmarcus]

What about a metro and a trailer? I have a buddy who's done some carpentry work for me and he's dropped off the trailer for a week or two. If you could use your truck only for towing when you had to, that could cut your fuel bill in half or less!

Also a belly pan and some aero wheel covers (if you don't mind getting heckeled by the guys at the jobsite!)

[ConnClark]

Originally Posted by mnmarcus

What about a metro and a trailer?

Aren't those words mutually exclusive?

[mnmarcus]

I meant a metro to DD to the trailer. (drop off the trailer with the truck)