My truck is 99 2500, Quad, 24V ,4WD 3. 54, Auto with 4" ex, Amsoil air filter and until yesterday no fueling mods. Basically stock for the last 50,000 miles I broke out all the tankfulls of fuel under 100% towing. It came out to 36 tanks of fuel. Truck with shell and full tank of fuel, 2 PAX weighs in at 7200 # and the trailer full up in the real world is 5000#. Trailer is an Airstream.
I take the time and fill it up to the top every fueling and generally do not refuel until I am close to 3/4 empty. I tow at an average of 68 MPH.
Highest MPG 15. 79 ( 55-60 MPH )
Lowest MPG 11. 9 ( 70-75 MPH, tooth ache headed home!!)
Average of 36 tanks 14. 30 MPG
Trivia to throw out for general information
I take the time and fill it up to the top every fueling and generally do not refuel until I am close to 3/4 empty. I tow at an average of 68 MPH.
Highest MPG 15. 79 ( 55-60 MPH )
Lowest MPG 11. 9 ( 70-75 MPH, tooth ache headed home!!)
Average of 36 tanks 14. 30 MPG
Trivia to throw out for general information
