I found a '95 250 stick-shift supercab 4X4 460 with 22,000 miles and finally gave up my old '84 250 diesel. It's taken some time to get used to the new truck but it's just what I was waiting for, no power windows or locks, or captain's chairs or other luxury frills, but a darn good farm or ranch work truck.
I've put about 6,000 miles on it so far and get 13-14 MPG unless I'm hauling a horse trailer up 9,000' passes (which is the norm here in northern New Mexico) then I get about 10 MPG.
Reading some of the earlier posts I guess I'm doing pretty good but with gas getting close to $3.00 a gallon I'd like to do better.
I just tried a code reader and and passed the KOEO but got 311 and 332 on the KOER. Could those effect milage?
The only noticible problem is an idle surge from normal of 1,000 to 1,500 rpm's that usually occurs after starting but sometimes when I'm driving in town. Could 311 and/or 332 be causing that?
Thanks very much for your help.

 

I'd say that's excellent mileage for a 460. You're not going to get much better than that with that truck unless you're going downhill all the time.