Ford Mustang (2005-2014) Owners Manual: Fuel quality

Note: Use of any fuel other than those recommended may cause powertrain damage and a loss of vehicle performance; repairs may not be covered under warranty.

Choosing the Right Fuel

Use only unleaded fuel or unleaded fuel blended with a maximum of 15% ethanol. Do not use fuel ethanol (E85), diesel fuel, fuel- methanol, leaded fuel or any other fuel because it could damage or impair the emission control system.

Octane Recommendations

• 3.7L V6 engine
Regular unleaded gasoline with a pump (R+M)/2 octane rating of 87 is recommended. Some stations offer fuels posted as Regular with an octane rating below 87, particularly in high altitude areas. Do not use fuels with octane posted on pump below 87.

• 5.0L V8 engine
Regular unleaded gasoline with a pump (R+M)/2 octane rating of 87 is recommended. Some stations offer fuels posted as “Regular” with an octane rating below 87, particularly in high altitude areas. Fuels with octane levels below 87 are not recommended. Do not use fuels with octane posted on pump below 87.

Premium fuel will provide improved performance and is recommended for severe duty usage, such as trailer tow.

• For Shelby GT500 octane requirements, see the Shelby GT500 Supplement.
Do not be concerned if your engine sometimes knocks lightly. However, if it knocks heavily while you are using fuel with the recommended octane rating, see your authorized dealer to prevent any engine damage.