FORD 2012 Shelby GT 500 v.2 - Manual (Page 292)

Choosing the right fuel
Use only UNLEADED fuel or UNLEADED fuel blended with a maximum
of 10% ethanol. Do not use fuel ethanol (E85), diesel, methanol, leaded
fuel or any other fuel. The use of leaded fuel is prohibited by law and
could damage your vehicle.
Your vehicle was not designed to use fuel or fuel additives with metallic
compounds, including manganese-based additives.
Note: Use of any fuel other than those recommended may cause
powertrain damage, a loss of vehicle performance, and repairs may not
be covered under warranty.
Octane recommendations
“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 be concerned if your engine sometimes knocks lightly. However, if
it knocks heavily under most driving conditions while you are using fuel
with the recommended octane rating, see your authorized dealer to
prevent any engine damage.
Octane recommendations (5.0L V8 engine)
ЉRegularЉ unleaded gasoline with a pump (R+M)/2 octane rating of 87 is
recommended. Some stations offer fuels posted as
ЉRegularЉ with an
octane rating below 87, particularly in high altitude areas. Fuels with
octane levels below 87 are not recommended. 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.
Fuel quality
If you are experiencing starting, rough idle or hesitation driveability problems
during a cold start, try a different brand of “Regular” unleaded gasoline.
Do not add aftermarket fuel additive products to your fuel tank. It should
not be necessary to add any aftermarket products to your fuel tank if you
continue to use high quality fuel of the recommended octane rating. These
products have not been approved for your engine and could cause damage
to the fuel system. Repairs to correct the effects of using an aftermarket
product in your fuel may not be covered by your warranty.
87
(R+M)/2 METHOD
Maintenance and Specifications
292
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