What are the thoughts on a Ram with 3.21 gears in a four door, 4x4, with either a 6 speed or 8 speed trans behind a Hemi? Talking 2013, 2014 or so years. The objective is fuel economy but not a dog. Rarely pull a trailer but on occasion could hook up an open car hauler with a 2 ton car. Current ride is a '02 5.9 quad cab with 3.55 gears. I like the '02 but tired of the poor fuel mileage, cracked dash and rust.