Is there a calculator that can approximate the expected MPG

Captain_Happy wrote:
Try dividing the gasoline used into the miles driven using an old school adding machine. Works every time.

0/0 = UNDEFINED

He is looking for a caculator to *PREDICT* the fuel economy of a yet-to-be-determined rig.

MH........SWAG is 6 mpg
Truck,,,gas.....SWAG is 8 mpg
Truck,,,diesel.....SWAG is 10mpg

The old 7.3 diesel averaged just shy of 13mpg but as low as 9mpg (into a 25mph headwind) and as high as 16mpg (30mph tail wind).

The new V10 doesn't have as many miles on it but seems to be running around 9mpg.

Way to much variation in rigs and how you drive to give a good estimate.

Try a crystal ball.

Budget 8mpg gas towing any high walled RV.
Budget 10mpg diesel towing any high walled RV.

You may get slightly better, but you will be much happier budgeting for 8 and getting 9 than budgeting for 10 and getting 9.

Weights do not matter (much). Every hill you go up you come back down. The fuel cost is for the aerodynamic drag at 65mph.