
How fail-safe cooling works
If the engine begins to overheat:
•The engine coolant temperature
gauge will move to the red (hot)
area.
•The
andsymbol will
illuminate.
•TheService Engine Soon
indicator light will illuminate.
If the engine reaches a preset
over-temperature condition, the engine will automatically switch to
alternating cylinder operation. Each disabled cylinder acts as an air
pump and cools the engine.
When this occurs the vehicle will still operate. However:
•The engine power will be limited.
•The air conditioning system will be disabled.
Continued operation will increase the engine temperature and the engine
will completely shut down, causing steering and braking effort to
increase.
Once the engine temperature cools, the engine can be re-started. Take
your vehicle to a service facility as soon as possible to minimize engine
damage.
When fail-safe mode is activated
You have limited engine power when in the fail-safe mode, so drive the
vehicle with caution. The vehicle will not be able to maintain high-speed
operation and the engine will run rough. Remember that the engine is
capable of completely shutting down automatically to prevent engine
damage, therefore:
1. Pull off the road as soon as safely possible and turn off the engine.
2. Arrange for the vehicle to be taken to a service facility.
3. If this is not possible, wait a short period for the engine to cool.
4. Check the coolant level and replenish if low.
Never remove the coolant reservoir cap while the engine is
running or hot.
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Maintenance and Specifications
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Repairs to correct the effects of using a fuel for which your vehicle was
not designed may not be covered by your warranty.
Octane recommendations
Your vehicle is designed to use
“Regular”unleaded gasoline with
pump (R+M)/2 octane rating of 87.
We do not recommend the use of
gasolines labeled as“Regular”that
are sold with octane ratings of 86 or lower in high altitude areas.
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 dealer or a qualified
service technician to prevent any engine damage.
Fuel quality
If you are experiencing starting, rough idle or hesitation driveability
problems during a cold start, try a different brand of unleaded gasoline.
“Premium”unleaded gasoline is not recommended for vehicles designed
to use“Regular”unleaded gasoline because it may cause these problems
to become more pronounced. If the problems persist, see your dealer or
a qualified service technician.
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. Aftermarket products 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.
Many of the world’s automakers approved the World-wide Fuel Charter
that recommends gasoline specifications to provide improved
performance and emission control system protection for your vehicle.
Gasolines that meet the World-wide Fuel Charter should be used when
available. Ask your fuel supplier about gasolines that meet the
World-wide Fuel Charter.
Cleaner air
Ford endorses the use of reformulated“cleaner-burning”gasolines to
improve air quality.
Running out of fuel
Avoid running out of fuel because this situation may have an adverse
affect on powertrain components.
87(R+M)/2 METHOD
2004 F250/350/450/550(f23)
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USA English(fus)
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249

Habits
•Smooth, moderate operation can yield up to 10% savings in fuel.
•Steady speeds without stopping will usually give the best fuel
economy.
•Idling for long periods of time (greater than one minute) may waste
fuel.
•Anticipate stopping; slowing down may eliminate the need to stop.
•Sudden or hard accelerations may reduce fuel economy.
•Slow down gradually.
•Driving at reasonable speeds (traveling at 88 km/h [55 mph] uses 15%
less fuel than traveling at 105 km/h [65 mph]).
•Revving the engine before turning it off may reduce fuel economy.
•Using the air conditioner or defroster may reduce fuel economy.
•You may want to turn off the speed control in hilly terrain if
unnecessary shifting between third and fourth gear occurs.
Unnecessary shifting of this type could result in reduced fuel
economy.
•Warming up a vehicle on cold mornings is not required and may
reduce fuel economy.
•Resting your foot on the brake pedal while driving may reduce fuel
economy.
•Combine errands and minimize stop-and-go driving.
Maintenance
•Keep tires properly inflated and use only recommended size.
•Operating a vehicle with the wheels out of alignment will reduce fuel
economy.
•Use recommended engine oil. Refer toLubricant specificationsin
this chapter.
•Perform all regularly scheduled maintenance items. Follow the
recommended maintenance schedule and owner maintenance checks
found in your vehicle scheduled maintenance guide.
Conditions
•Heavily loading a vehicle or towing a trailer may reduce fuel economy
at any speed.
•Carrying unnecessary weight may reduce fuel economy (approximately
0.4 km/L [1 mpg] is lost for every 180 kg [400 lb] of weight carried).
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Temperature A B C
The temperature grades are A (the highest), B and C, representing the
tire’s resistance to the generation of heat and its ability to dissipate heat
when tested under controlled conditions on a specified indoor laboratory
test wheel. Sustained high temperature can cause the material of the tire
to degenerate and reduce tire life, and excessive temperature can lead to
sudden tire failure. The grade C corresponds to a level of performance
which all passenger car tires must meet under the Federal Motor Vehicle
Safety Standard No. 109. Grades B and A represent higher levels of
performance on the laboratory test wheel than the minimum required by
law.
The temperature grade for this tire is established for a tire that
is properly inflated and not overloaded. Excessive speed,
underinflation, or excessive loading, either separately or in
combination, can cause heat buildup and possible tire failure.
TIRES
Tires are designed to give many thousands of miles of service, but they
must be maintained in order to get the maximum benefit from them.
Glossary of tire terminology
•Tire label:A label showing the OE (Original Equipment) tire sizes,
recommended inflation pressure and the maximum weight the vehicle
can carry.
•Tire Identification Number (TIN):A number on the sidewall of
each tire providing information about the tire brand and
manufacturing plant, tire size and date of manufacturer.
•Inflation pressure:A measure of the amount of air in a tire.
•Standard load:A class of P-metric or Metric tires designed to carry a
maximum load at 35 psi [37 psi (2.5 bar) for Metric tires]. Increasing
the inflation pressure beyond this pressure will not increase the tires
load carrying capability.
•Extra load:A class of P-metric or Metric tires designed to carry a
heavier maximum load at 41 psi [43 psi (2.9 bar) for Metric tires].
Increasing the inflation pressure beyond this pressure will not increase
the tires load carrying capability.
•kPa:Kilopascal, a metric unit of air pressure.
•PSI:Pounds per square inch, a standard unit of air pressure.
2004 F250/350/450/550(f23)
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Sometimes irregular tire wear can be corrected by rotating the tires.
Note:If your tires show uneven wear ask a qualified technician at a
reputable repair facility to check for and correct any wheel misalignment,
tire imbalance or mechanical problem involved before tire rotation.
Tire wear
Measure and inspect the tire tread on all your tires periodically.
Advanced and unusual tire wear can reduce the ability of tread to grip
the road in adverse (wet, snowy, etc.) conditions. Visually check your
tires for uneven wear, looking for high and low areas or unusually
smooth areas. Also check for signs of tire damage.
When the tread is worn down to 4
mm (1/16th of an inch), tires must
be replaced to prevent your vehicle
from skidding and hydroplaning.
Built-in treadwear indicators, or
“wear bars”, which look like narrow
strips of smooth rubber across the
tread will appear on the tire when
the tread is worn down to 4mm (1/16th of an inch). When you see these
“wear bars”, the tire is worn out and should be replaced.
Inspect your tires frequently for any of the following conditions and
replace them if one or more of the following conditions exist:
•Fabric showing through the tire rubber
•Bulges in the tread or sidewalls
•Cracks or cuts on the sidewalls
•Cracks in the tread groove
•Impact damage resulting from use
•Separation in the tread
•Separation in the sidewall
•Severe abrasion on the sidewall
If your vehicle has a leak in the exhaust system, a road tire or the spare
tire may be exposed to hot exhaust temperatures requiring the tire to be
replaced.
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recommendations ...................237
refill capacities ........................278
specifications ..................281, 284
Exhaust fumes ..........................128
F
Fail safe cooling ........................244
Fluid capacities .........................278
Foglamps .....................................41
Four-Wheel Drive vehicles .......143
description ..............................147
driving off road .......................149
electronic shift ................143, 147
indicator light .........................144
lever operated shift ................145
manual locking hubs ..............143
preparing to drive your
vehicle .....................................131
Fuel ............................................246
calculating fuel economy .......250
cap ...........................................248
capacity ...................................278
choosing the right fuel ...........248
comparisons with EPA fuel
economy estimates .................253
detergent in fuel .....................249
filling your vehicle with
fuel ...........................246, 248, 250
filter, specifications ........250, 277
fuel pump shut-off switch .....192
improving fuel economy ........250
octane rating ...................249, 284
quality ......................................249
running out of fuel .................249
safety information relating to
automotive fuels .....................246
Fuel pump shut-off switch .......192
Fuses ..................................193–194
G
Garage door opener ....................53Garage Door Opener
(see Homelink wireless
control system) ...........................62
Gas cap (see Fuel cap) ............248
Gas mileage
(see Fuel economy) .................250
Gauges .........................................15
transmission fluid
temperature gauge ...................19
GAWR
(Gross Axle Weight Rating)
calculating ...............................162
GVWR
(Gross Vehicle Weight Rating)
calculating ...............................162
H
Hazard flashers .........................192
Head restraints ...........................89
Headlamps ...................................40
aiming ........................................43
autolamp system .......................40
daytime running lights .............41
flash to pass ..............................42
high beam .................................42
replacing bulbs ...................45–46
turning on and off ....................40
Heating
heating and air conditioning
system .................................37–38
HomeLink universal
transceiver
(see Garage door opener) .........65
Homelink wireless control
system ..........................................62
Hood ..........................................233
I
Ignition ...............................124, 284
2004 F250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA English(fus)
Index
301