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.
I don't really calculate the MPGs any more. It's It varies from somewhere in the 40s to somewhere in the 50s, depending on the use of the energy that I stored from the grid. A trip that stays in EV mode uses no gas at all. A trip that is 100% gentle down hill grade at 55 MPH uses very little gas. There is a display that shows the MPG on the screen, but I know that it's a mixture of the EV and gas modes.
I'm not sure that it's all that huge nor heavy. From the net: 3,571 lbs for the XSE Premium Prime. The 2015 Prius weighed in at 3,072 pounds, so that's a 500 lb difference to provide a much, much, snappier response. Since that's the same weight as a 2024 Camry hybrid, the "huge and heavy" are pretty much not applicable. It's not like it's a 4,398 lbs Tesla Model Y.
Yeah 80 MPH with bike rack on the outside is not the Prius sweet spot. I'd not use this scenario to judge being concerned or not. On mine, I've seen low 40s on long highway drives 75MPH+, etc. I'd say sweet spot is 55-65MPH. Anything over 65 and your MPG will suffer.
