I have a '95 Toyota 4-runner with a 3.0 engine. It is giving me 15 m.p.g. with little hiway travel, some rough dirt roads, some 4X4 and rural traffic. All mileage is put in under or at the speed limit. Can I do better than this? I owned a Buick Century Wagon up until last November when some bozo in a big truck rear ended and totalled it. The Century was giving me 22 or more m.p.g. and it had the same sized engine and was of the same year. In fact, my Toyota engine was recently rebuilt. When they did this they didn't replace the wires and I assume they did replace the plugs. Otherwise, I've made sure it has been tuned properly. I also keep the tires correctly inflated. Should I expect better mileage? Can I do something else to improve it? I know that I'm not alone in this quest.