There are a few things you can do to the 440 to get better mileage but it's not going to beat 5.2 or 5.9. I would strongly suggest to wait for a A500 or similar (46RH)! Not only overdrive but a lock up converter. The lock up converter cuts 200 rpms off when it's engaged. My power wagon has just a 727 and a 360 with 3.55 and 31's and you don't even think about getting on an express way. You will be doing 3K+ and cars will fly by you where a A500/46RE will like 1.2K and keeping up with traffic. Not to mention the gas usage difference.