Diesel been over $4.00 a gallon since last November But its gasoline that went down sharply right around November and continues to fall. I found another fuel station at $3.389 fo gas and $4.429 for diesel.
As for comparing the 2 rigs... Fuel log histories...
2002 Dodge Ram 2500 5.9L Cummins Turbo Diesel (7,300#)
Lowest 14.1 MPG - Highest 25.3 MPG
1996 Dodge Ram 1500 5.9L V8 (5,500#)
Lowest 6.30 MPG - Highest 16.16 MPG
Even my worse MPG in the 2002 is still above the average for the 1996 Dodge. As for records for the 96 Dodge there is very little data because it was a stand in truck for many years. Now the 96 Dodge just became the daily driver.
Then if I want to be cruel I could go off and figure it out in Mile Per Gallon Per Ton and the Cummins will still have a higher score that the 96 Dodge hands down...