I had a '98 3/4 ton 454 Suburban pulling a Cougar 305BHS TT weighing about 9500# and got 8+ MPG. I upgraded to an '01 PSD Excursion with A&E intake,DP tuner and 4" turbo back exhaust and improved to 10.5 MPG. Then 4 years ago,I bought my Tradewinds 7390 with the 330 Cat turbo and who cares about the mileage, 'cuz as said before it's what we wanted and could afford. I get from 6-8 mpg hand calculated and that's fine.Ran it thru the Cat shop a bit ago for an IAPVC and they downloaded the computer and it read that I was getting 7.5 mpg for the life of the MH on the road and 7.2 overall. That's for an '01 rig with 108K on the odometer.