There's no single answer to whether Ford or Chevy vehicles get better gas mileage. Gas mileage varies dramatically depending on the *specific model*, *year*, *engine*, *drivetrain* (2WD vs. 4WD), and even options like tire size. A fuel-efficient Ford hybrid could easily outperform a gas-guzzling Chevy truck.
To compare gas mileage, you need to specify the exact makes and models you're interested in and then check the EPA's fueleconomy.gov website or the manufacturer's website for their fuel economy ratings.
