I don't know the difference but I live in Reno NV and do mostly high speed driving on my 26 Lariat. Last tank I got 34.5 mpg. Truck has 1000 miles on it.
My dad bought a new Dodge car back in the 60's that had a bad rattle in the front seat. They found an empty pint bottle of Jack Daniel's wedged under the backrest cushion.