The problem with bed covers is that they don't really clean up much because the drop from the cab to the bed has already seperated the airflow from the top/side. I'd go for underbody/rear wheel covers, a campershell, and maybe airtabs all around. A WAI will only hurt a diesel, but if you really wanted to, a post intercooler water injection system should help out with FE and power. If you can stand it, and had the cruise control at 60mph, try 55mph. You should see ~21-22mpg.
Originally Posted by FormulaTwo
I think if i could get that type of FE i would have no problem driving a dildo shaped car.
My '79 F250 crosses the scales at about 4600. That's really light these days... like a stripped half ton. With a few common accessories (like a bed-mounted diesel tank), the newer trucks tare over 8000.
Old thread I know but the nice thing about the old International diesels Ford used is you can pour just about anything in the fuel tanks that will burn.
A buddy of mine in Dallas siphons off oil from a waste oil recycling container and adds a gallon or so of E85 to it and pours that straight into the tank and then tops the tank off with a little diesel. He says it's a little harder to start since he is running 50-75% god knows what oil mix and it is winter but once you get going it runs great and is actually getting better mileage than straight diesel does.