It may not be a 40 gallon tank. According to the spec sheets/brochures we thought we had a 40 gallon tank on our Octane (even the dealership told us it was a 40 gallon tank). Had a similar issue the first time we filled the fuel tank/station up. It only took 30 gallons. After contacting Jayco with the Vin# they let me know we only have a 32 gallon fuel tank.
We are just a humble drinking couple with a hunting and camping problem.
2018 Jayco Octane 260
2004 Dodge Ram 2500, 5.7 Hemi, 5Spd Manual
2018 Argo Frontier 8x8/2008 Arctic Cat M1000 SnoPro
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