Diesel Bombers - Terrific Idea, Well Maybe

Here's the story. I'm trying to save gas in a fuel efficent vehicle, not in my truck and it's not that I don't love my truck, gas is going up and I want to save money. I would only need the GMC to pull my boat and tractor here and there and I don't always do that. And that's were my "terrific" idea comes into play. To conserive on gas i've started looking around for a geo tracker/mitsubishi mightymax pickup. The mightymax got about 25-28 mpg but it also burn about a quart and a half of oil between fillups. Needless to say that truck was a pos. The tracker, I'm not so sure about. I looked in the carolina trader and found one for about 800 bucks, I figrued if i kept it to a 2wd 4cyl. manual truck i would have a gas saver. If yall have any bad experences with the tracker or an alternative to these smaller trucks post it. If yall have any alternative truck let me know. Oh and it has to be under one grand. Thanks alot guys.