I fully charge a 2021 Ford Mustang Mach-E AWD with the Extended Range battery option to see how far it will go at a constant 70 mph. It has 98.8 kWh of total energy, of which 88 kWH is usable.

The temperature was in the high 60's when I started and got up to a peak of 74 degrees. The average temperature was above 70 F for the duration of the drive.

I was able to drive the Mach-E 282 miles before the state of charge hit zero, and at that point, the range estimator showed I could drive an additional 3 miles.

This version of the Mach-E has a combined EPA range rating of 270 miles. The highway range rating was 249 miles. Needless to say, The Mach-E way outperformed its EPA range rating, which is rare for electric vehicles to do.

I'm sure the results would have been different if the weather was colder, as the Mach-E doesn't employ an efficient heat pump for better cold-weather range, so the penalty for using the resistive heating system would likely be significant.

Check out some of my other EV 70-mph highway range tests.

2019 Tesla Model 3:    • Tesla Model 3 Highway Range Test @70 mph  
2020 Porsche Taycan 4S:    • 2020 Porsche Taycan 4S Cold Weather H...  
2020 Chevy Bolt EV:    • 2020 Chevy Bolt EV Highway Range Test...  
2020 Tesla Model Y:    • 2020 Tesla Model Y 70-mph Highway Ran...  
2020 Nissan LEAF SL Plus:    • 2020 Nissan LEAF SL Plus Highway Rang...  
2020 Hyundai Kona Electric:    • 2020 Hyundai Kona Electric 70 mph Hig...