Hi. Where are you, so I can come kick you in the nuts.
Kidding, sorta. I'm elated when I get a range over 400.
Don't we have the same truck? You should easily have a 500+ mile range. I had some fun with a friend who'd just bought an Equinox, and was bragging that he had a 500-mile range. I just said, "Well, so do I."
A little over a year ago had to drive down to Atlanta, so I filled the tank and headed out. I hit Cincinnati in my usual 4 hours flat, and felt pretty good, so I decided to see how far I could go on one tank of gas. The mistake I made was that I was watching the distance to empty calculation to plan my stop, and wasn't paying attention to the miles driven. Even though the computer said I had 77 miles to empty, I ran out of gas. I had driven 586 miles, which worked out to almost exactly 15 mpg.
I don't have the patience to drive on long trips at a sedate pace. I'm using Waze, watching for cops, and whenever someone passes me at a high rate of speed, I'll drop in behind them and use them as a blocker. So for me, 15 mpg on the highway is great, because I'm usually averaging 80-90 MPH.
If I did have the patience, and because of the 39-gallon tank, I could probably go over 600 miles if I could leave the cruise set at 65 or something like that.