I recently purchased a 1988 Ford F350 460 manual trans truck. It was in pretty bad shape but it ran. After working out all the major issues I found that the fuel mileage was alot woarse then expected. 7MPG bad on the open road. I can live with 10-12MPG, but 7! I have no clue to why it is so bad. If anyone has any advice I would really appreciate it. One thing that is a bit wierd too, is the truck pasted smog even with this issue.

Thanks