Question: are mustangs good on gas?
Answer: Ford Mustang MPG & CO2 The most efficient and cheapest-to-run version of the Mustang is the entry-level 2.3 EcoBoost with a six-speed manual gearbox. It's still not great, however, with official tests promising average fuel economy of 31.7mpg. Choose an automatic gearbox and this drops to just 30.7mpg.