With YYSKI... I have a 99 2wd with the 5.9. I get his same numbers. what I do like is that it doesn't loose much towing. I hauled my 69 GTX from Florida to Columbus (Mopar Nats) on an open trailer running 80mph on flat land and 75 through the mountains and got 12 mpg. I found my self towing same said GTX at 94mph down the Fl turnpike once....Yeah yeah I know... slow down!