Yeah, which I found strange, since I pretty much had the cruise engaged at 70
mph the whole way. Supposedly, the GPS in the Navi is a more accurate depiction of speed. Perhaps I should get my speedo calibrated, since I generally drive at the limits of most officer's crossover point of writing a ticket or letting it go. I usually do about 5
mph over. Sometimes 10. If I'm doing a speedo speed of 70 in a 60, but the police radar shows me at 72...
A story about my 600+ tank: I filled up just north of Denver. Then I drove down to Albuquerque and started to head West. I see that my FE is doing pretty good, so instead of filling up just over 500+, I decide to go for the 600+ tank! I'm thinking, I just might make it to Gallup! Out on the high plains of Northern NM and AZ, the gas stations are far and few between. So, every time I pass a gas station, I get more and more worried about running out of fuel.

At 547 miles, my low fuel indicator comes on.
Okay, I can do this! 575 miles, oh man. That needle is pointing STRAIGHT at the E indicator! Come on baby, you can do it!! 585, I'm starting to sweat it. 590, oh crap. I just KNOW I'm walking. 595, "dear father who art in heaven..." 599, okay three miles to go to get to the Chevron! I can do this! (just past a sign that says next station is something like 20 miles away, past the Chevron) 600, WOHOO!! 602, here's my exit! YES! I made it! The needle is slightly south of the E mark. Hell, at this speed, I could just coast into the station, if need be. But then my world darkened. As I exit, I notice there aren't any cars at the gas station. There are cones blocking off the driveway into the pumps. NOOOOOOO! Oh God, will I make it another 20 miles?! But as I pull up to the station, the second driveway was open. And the OPEN sign was lit in the gas station window. YES! I pull up to the pump, relieved that my nightmare was finally over.
14.23 gallons later, I realized, I definitely had plenty of fuel to make it to not only the next gas station 20 miles away, but probably to the one after that! Whew, what a relief. I can't remember what exactly my FCD said I had distance to empty. I think it said something around 30+ miles. Nonetheless, I had plenty of fuel to make the trip. But never being this deep into a tank, I had no clue...