Extracted data from CfgVehicles using my snippet above:
"Land_FuelStation_Feed_F: 50000l",
"Land_fs_feed_F: 50000l",
"Bomb: 50000l",
"B_APC_Tracked_01_CRV_F: 3000l",
"B_Truck_01_fuel_F: 1e+012l",
"Truck_02_fuel_base_F: 1e+012l",
"O_Truck_02_fuel_F: 1e+012l",
"I_Truck_02_fuel_F: 1e+012l",
"C_Truck_02_fuel_F: 1e+012l",
"C_Van_01_fuel_F: 1e+012l",
"I_G_Van_01_fuel_F: 1e+012l",
"B_G_Van_01_fuel_F: 1e+012l",
"O_G_Van_01_fuel_F: 1e+012l",
"C_Van_01_fuel_white_F: 1e+012l",
"C_Van_01_fuel_red_F: 1e+012l",
"C_Van_01_fuel_white_v2_F: 1e+012l",
"C_Van_01_fuel_red_v2_F: 1e+012l",
"Land_StorageBladder_01_F: 60000l",
"StorageBladder_01_fuel_forest_F: 60000l",
"StorageBladder_01_fuel_sand_F: 60000l",
"Land_FlexibleTank_01_F: 300l",
"FlexibleTank_01_forest_F: 300l",
"FlexibleTank_01_sand_F: 300l",
"B_Slingload_01_Fuel_F: 1e+012l",
"O_Heli_Transport_04_fuel_F: 3000l",
"Land_Pod_Heli_Transport_04_fuel_F: 3000l",
"O_Heli_Transport_04_fuel_black_F: 3000l",
"Land_Pod_Heli_Transport_04_fuel_black_F: 3000l",
"O_Truck_03_fuel_F: 3000l","Land_FuelStation_01_pump_F: 50000l",
"Land_FuelStation_02_pump_F: 50000l",
"B_T_APC_Tracked_01_CRV_F: 3000l",
"B_T_Truck_01_fuel_F: 1e+012l",
"O_T_Truck_03_fuel_ghex_F: 3000l"
Now here are my suggestions for a more authentic configuration considering physical size and real life counterparts of the corresponding vehicles:
Small fuel trucks based on "B_G_Van_01_fuel_F": 3785l
Large fuel trucks similar to "O_Truck_03_fuel_F" / "B_Truck_01_fuel_F" / "C_Truck_02_fuel_F": 11000l
Small fuel barrels similar to "FlexibleTank_01_sand_F" / "FlexibleTank_01_forest_F": 60l (there's no way these could hold 300l)
And finally please configure the fuel can to have 10l of fuel.
Please adjust those values to reasonable amount, not only fuel but also consider adjusting ammo/repair.
Changed it due to the exploitable nature of this regarding the bobcat example given above.