octane FORD F-650/750 2018 Owners Manual

Do not use alcohol-based additives to
improve cetane quality, to prevent fuel
gelling or any other use. The use of alcohol
additives may result in damage to the fuel
injectors and system. See Capacities and
Specifications (page 261).
The Vehicle Warranty may not cover
repairs needed to correct the effects of
using an aftermarket product that does
not meet Ford specifications in your fuel.
FUEL QUALITY - GASOLINE
Choosing the Right Fuel Your vehicle is designed to operate on
regular unleaded gasoline with a minimum
pump (R+M)/2 octane rating of 87. Some
fuel stations, particularly those in high
altitude areas, offer fuels posted as regular
unleaded gasoline with an octane rating
below 87. We do not recommend these
fuels. For best overall vehicle and engine
performance, premium fuel with an octane
rating of 91 or higher is recommended. The
performance gained by using premium fuel
is most noticeable in hot weather as well
as other conditions, for example when
towing a trailer. See
Towing a Trailer
(page 143).
Do not use any fuel other than those
recommended because they could lead to
engine damage that may not be covered
by the vehicle Warranty. Note:
Use of any fuel other than those
recommended can impair the emission
control system and cause a loss of vehicle
performance.
Do not use:
• Diesel fuel.
• Fuels containing kerosene or paraffin.
• Fuel containing more than 10% ethanol
or E85 fuel.
• Fuels containing methanol.
• Fuels containing metallic-based
additives, including manganese-based
compounds.
• Fuels containing the octane booster
additive, methylcyclopentadienyl
manganese tricarbonyl (MMT).
• Leaded fuel (using leaded fuel is
prohibited by law).
The use of fuels with metallic compounds
such as methylcyclopentadienyl
manganese tricarbonyl (commonly known
as MMT), which is a manganese-based
fuel additive, will impair engine
performance and affect the emission
control system.
Do not be concerned if the engine
sometimes knocks lightly. However, if the
engine knocks heavily while using fuel with
the recommended octane rating, contact
an authorized dealer to prevent any engine
damage.
RUNNING OUT OF FUEL -
DIESEL
Avoid running out of fuel. This allows air to
enter the fuel system and may make it
difficult to restart your vehicle.
96
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Dual Alternator Dual Alternator With Air Brake
Compressor
Drivebelt closest to the engine.
A
Drivebelt furthest from the
engine.
B
Note: The belt routings show vehicles
equipped with air conditioning. When not
equipped with air conditioning a idler pulley
is in place of the A/C compressor.
ENGINE SPECIFICATIONS - 6.8L 6.8L V10 Engine
Engine
413
Cubic inches
Minimum 87 octane
Required fuel
1-6-5-10-2-7-3-8-4-9
Firing order
Coil on plug
Ignition system
0.039 - 0.043 in (1.00 - 1.10 mm)
Spark plug gap
9.2:1
Compression ratio
256
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