* 16 gallons: This was the standard size for most models.
* 15.7 gallons: Some models, particularly those with certain options, might have had a slightly smaller 15.7-gallon tank.
To be absolutely certain of the size for a specific 2008 Mustang, check the vehicle's sticker located inside the driver's side doorjamb. This sticker will list the vehicle's specifications, including the fuel tank capacity.
