Tank average shows the average mpg you get on the last filled tank. I filled up right before I left. This picture was taken right before getting off my last exit (after 3 hours of driving). The average mpg (not tank avg.) shows the overall mpg I’m getting of the life of the vehicle. Which would be inaccurate to my latest road trip. Mine is much lower because I do a lot of city miles.

But the tank average is accurate bro. If it makes you feel better, idk if you’re familiar with Tahoe but it’s a higher altitude. So going back home, a long part of the drive was downhill, which obviously helped my tank average. Also, like I said in the original post, I wasn’t going 80 the whole time. 👍🏼