Just changed the oil and filter on my 2025 XLE with the odometer at 600 miles. I then drove from Orange County in SoCal to San Raphael in the Bay Area, a distance of about 450 miles. My route took me along the 405, 5 and 580 freeways. The 5 fwy has some pretty good climbs before dropping down into the CA central valley, and similarly the 580 has some good elevation approaching the Bay Area. I set my ACC to 80 mph (pretty much what traffic was doing in the fast lane). I had a hitch mounted bike rack with a mountain bike loaded up on it, which seriously effs with the aerodynamics of the car. The car returned 35 mpg for the trip!! Should I be concerned? Thoughts....
Like many cars, it's MPG is directly impacted by the MPH and the terrain. I made the same trip this weekend in a 2024 XSE Prime. I drove at the escalated speed of 75 to 85 MPH. I normally make it from the gas station at the base of the grapevine to the Altamont Pass without running low on gas or electricity. I pulled into the corner gas station with only a few miles of gasoline range left. The traction battery still had 20% of it's remaining capacity as we pulled into the driveway. In general, if you want good mileage, don't drive into a headwind. Use the cruise control to moderate your use of gas.
IMHO; that's kinda expected doing 80 mph with the additional wind drag of the bike on a rack. That bike back there acted like a drag parachute. Arriving with 20% traction battery remaining means that you weren't coasting much or using the battery much - that was pretty much all 2.0L motor dragging that huge heavy car. Was the car in ECO mode? I'd wager the mpg will move up to it's normal average on your normal commute.
