Hello, I have some confusion. I have a 2007 entourage for about a year, and today I was driving after the fuel light came on for about 30 miles because I had an appointment I was running late for. I then got gas and filled up with 17.911 US gallons. My owners manual says it is 21.1 US Gallons 17.6 imperial gallons, and everywhere I look online says the same. I am in the US so I think I should have been closer to 21 gallons being that I drove that far after the light came on. Surely I don’t have like 4 gallons after the light comes on, do I?