Gross and net are two ways to count the same fuel. Gross is the gallons as actually measured in the truck. Net is those gallons corrected to a standard temperature of 60 degrees.
Fuel expands when it is warm and shrinks when it is cold, so the same amount of fuel measures more gallons hot and fewer gallons cold. To keep that swing from confusing the count, the trade also figures the volume the fuel would fill at 60 degrees. The raw measured number is gross gallons. The temperature-corrected number is net gallons.
On a warm load the gross figure is higher than the net, because the fuel is puffed up by heat. On a cold load it is the reverse. The fuel is the same either way. Only the count changes.
Which number a deal uses can quietly decide who comes out ahead. If you buy on gross and sell on net, warm fuel can leave you paying for gallons that were never really there. Most terminal loads are billed on net for that reason, and a jobber watches closely to make sure it buys and sells on the same basis.
In useThe load showed 8,540 gross gallons but 8,500 net on the ticket, so the jobber billed the customer on net to match what it actually paid the terminal.
See also Bill of lading (BOL), Shrinkage, Lifting