Drove to Sunshine village and back with the truck today. Just for kicks, I filled up in the morning and again in the afternoon so I could calculate my mileage.
According to the odometer, I drove a distance of 175.3 miles, and I burned 52.678 l of gas (works out to 13.916 us gal). And just in case you were wondering, Google maps agrees with the distance.

That puts my 77 460 supercab right at 12.6 mpg. Obviously this is a best case scenario, since it was all unloaded highway driving, but I was honestly expecting worse. The guy I bought it from last spring must have had it tuned right up!

I don't think I'll ever check it again, I don't want to burst this bubble.

 

I think that is pretty good considering you have a big block, some of us guys with the modular v8's get just a fraction more than you.

 

That is not bad at all for a big ol 460!

 

Yep, I'm really pleased.

 

I'd be happy with that. I am like you, once I get a good reading, I never look back. I like living in my bubble.