Flex fuel vehicle (FFV) fuel fill inlet
Flex fuel vehicles have a yellow bezel placed over the fuel fill inlet.
Choosing the right fuel
Use only UNLEADED FUEL and FUEL ETHANOL (Ed75–Ed85).
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
Your vehicle is designed to use “Regular” unleaded gasoline with a pump
(R+M)/2 octane rating of 87. 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.
FFV engines
Your vehicle is designed to use Fuel Ethanol (Ed75–Ed85),“Regular”
unleaded gasoline or any mixture of the two fuels.
Use of other fuels such as Fuel Methanol may cause powertrain
damage, a loss of vehicle performance, and your warranty may be
invalidated.
It is best not to alternate repeatedly between gasoline and E85. If you do
switch fuels, it is recommended that you add as much fuel as
possible—at least half a tank. Do not add less than five gallons (18.9L)
when refueling. You should drive the vehicle immediately after refueling
for at least 5 miles (8 km) to allow the vehicle to adapt to the change in
ethanol concentration.
If you exclusively use E85 fuel, it is recommended to fill the fuel tank
with regular unleaded gasoline at each scheduled oil change.
87
(R+M)/2 METHOD
Maintenance and Specifications
315
2011 Navigator
(nav)
Owners Guide, 1st Printing
USA
(fus)
