I have a 78 Blazer, 4wd, automatic with a 350. It is equiped as a trailering special with 4.10 gears front and rear and gets roughly 8 to 10 mpg at 55 mph. I want to gear it up to gain better gas mileage and was wanting to know if anyone has done a similar gear swap and what kind of results they gained? Load pulling ability is not an issue since I don't have anything to pull anyhow. Thanks for any input.