I've got a little over 800 miles on my GX550 Overtrail and about half has been highway driving at 60-65 mph and rest in the city. About 75% of the time i've been running 93 octane in it (from Costco), and remainder of the time using 91 octane from Top Tier gasoline brands. Average mpg to date for the highway driving is 21.3 mpg and for city driving is 17.8 mpg. [NOTE: I've been using the Eco Mode for nearly all of the 800 miles so far, and i don't have a lead foot and tend to only gun it on highway ramps/merging and passing on 2-lane roads]. So far i'm very pleased with the gas consumption of the GX550...it's a heck of a lot better than what my 2016 Land Cruiser got (i.e., 12-13 mpg city and 15-17 mpg highway).Some of my complaints so far with the Lexus GX550
- It gets pretty terrible gas mileage, 13mpg, I wish it had a larger fuel tank, ~250mi range
- I wish it had starlink roam instead of att wireless
- I can't figure out how to turn on the massage seats
- I wish the 2nd row was a few inches pushed back, using a rotating car seat is impossible
- I wish it had more leg room for the first row passenger
Other than that I like it a lot