series 60 mileage and speed

[DOSZORROS]

My pro driver is TU but I have always logged all fuel in and all miles run (survival habit from my bush flying days). I averaged 6 to 6.2 mpg on my 96 bird with a series 60 and I average 6 to 6.4 with my 2003 LXI with a series 60. I always tow and load heavy.

This mileage is logged over a many thousands of miles and includes start up time, cool down time, aquahot and generator time. This is the actual mileage I use to plan trips.

Mileage minders (not singling out the pro driver), primarily in my diesel pickup experience, can be terrible liars. We bought a new 2009 GMC Duramax pickup, put in an aftermarket mileage computer, made two trips to Alaska and back and then put in the OEM computer and made the same trip to Alaska and back.

The after market mileage computer showed we were getting 3 mpg better mileage than the OEM computer. The logged fuel and mileage indicated exactly the same. Go figure!