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3. The fuel cap may not have been securely tightened.
These temporary malfunctions can be corrected by filling the fuel tank
with good quality fuel and/or properly tightening the fuel cap. After three
driving cycles without these or any other temporary malfunctions
present, theCheck Engine/Service Engine Soonlight should turn off.
(A driving cycle consists of a cold engine startup followed by mixed
city/highway driving.) No additional vehicle service is required.
If theCheck Engine/Service Engine Soonlight remains on, have your
vehicle serviced at the first available opportunity.
Readiness for Inspection/Maintenance (I/M) testing
In some localities, it may be a legal requirement to pass an I/M test of
the on-board diagnostics system. If your“Check Engine/Service Engine
Soon”light is on, refer to the description in theWarning lights and
chimessection of theInstrument clusterchapter. Your vehicle may not
pass the I/M test with the“Check Engine/Service Engine Soon”light on.
If the vehicle’s powertrain system or its battery has just been serviced,
the on-board diagnostics system is reset to a“not ready for I/M test”
condition. To ready the on-board diagnostics system for I/M testing, a
minimum of 30 minutes of city and highway driving is necessary as
described below:
•First, at least 10 minutes of driving on an expressway or highway.
•Next, at least 20 minutes driving in stop-and-go, city-type traffic with
at least four idle periods.
Allow the vehicle to sit for at least eight hours without starting the
engine. Then, start the engine and complete the above driving cycle. The
engine must warm up to its normal operating temperature. Once started,
do not turn off the engine until the above driving cycle is complete.
2003 F250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
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Make sure that all replacement tires are of the same size, type,
speed rating, load-carrying capacity and tread design (e.g.,“All
Terrain”,“Touring”, etc.), as originally offered by Ford.
Do not replace your tires with“high performance”tires or larger
size tires.
Failure to follow these precautions may adversely affect the
handling of the vehicle, and increase the risk of loss of vehicle
control, vehicle rollover and/or personal injury.
Tires that are larger or smaller than your vehicle’s original tires may also
affect the accuracy of your speedometer.
SNOW TIRES AND CHAINS
Snow tires must be the same size and grade as the tires you
currently have on your vehicle.
The tires on your vehicle have all weather treads to provide traction in
rain and snow. However, in some climates, you may need to use snow
tires and chains. If you need to use chains, it is recommended that steel
wheels (of the same size and specifications) be used, as chains may chip
aluminum wheels.
Follow these guidelines when using snow tires and chains:
•Use only SAE Class S chains.
•Install chains securely, verifying that the chains do not touch any
wiring, brake lines or fuel lines.
•Drive cautiously. If you hear the chains rub or bang against your
vehicle, stop and re-tighten the chains. If this does not work, remove
the chains to prevent damage to your vehicle.
•If possible, avoid fully loading your vehicle.
•Remove the tire chains when they are no longer needed. Do not use
tire chains on dry roads.
•The suspension insulation and bumpers will help prevent vehicle
damage. Do not remove these components from your vehicle when
using snow tires and chains.
2003 F250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
252
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Fluid Ford Part Name Application Capacity
Fuel tank N/A Mid-ship tank
(optional on
Chassis Cab)71.9L (19.0
gallons)
Right side
saddle mounted
tank (optional
on Chassis Cab)87.1L (23.0
gallons)
Short box 109.8L (29.0
gallons)
Long box 143.9L (38.0
gallons)
Aft axle 151.4L (40.0
gallons)
Power steering
fluidMotorcraft
MERCONAT FAll Fill to FULL
COLD range on
dipstick
Transfer case
fluidMotorcraft
MERCONAT F4x4 vehicles 1.9L (2.0
quarts)
Manual
transmission
fluidMotorcraft
MERCONAT F6-speed manual 5.5L (5.8
quarts)
5
Automatic
transmission
fluid
4
Motorcraft
MERCONAT F4R100
(4–speed)16.7L (17.7
quarts)6
Motorcraft
MERCONSP ATFTorqShift
(5–speed)16.6L (17.5
quarts)
6(includes
remote filter
element
change)
Windshield
washer fluidMotorcraft
Premium
Windshield Washer
ConcentrateAll 4.0L (4.25
quarts)
2003 F250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
255
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filter, specifications ........220, 253
recommendations ...................220
refill capacities ........................254
specifications ..................257, 260
Exhaust fumes ..........................114
F
Fail safe cooling ........................227
Fluid capacities .........................254
Foglamps .....................................39
Four-Wheel Drive vehicles .......129
description ..............................133
driving off road .......................135
electronic shift ................129, 133
indicator light .........................130
lever operated shift ................130
manual locking hubs ..............129
preparing to drive your
vehicle .....................................117
Fuel ............................................229
calculating fuel economy .......233
cap ...........................................231
capacity ...................................254
choosing the right fuel ...........231
comparisons with EPA fuel
economy estimates .................236
detergent in fuel .....................232
filling your vehicle
with fuel ..................229, 231, 233
filter, specifications ........233, 253
fuel pump shut-off switch .....175
improving fuel economy ........233
octane rating ...................232, 260
quality ......................................232
running out of fuel .................232
safety information relating to
automotive fuels .....................229
Fuel pump shut-off switch .......175
Fuses ..................................176–177G
Garage door opener ....................50
Gas cap (see Fuel cap) ............231
Gas mileage
(see Fuel economy) .................233
Gauges .........................................15
transmission fluid
temperature gauge ...................19
GAWR
(Gross Axle Weight Rating) .....145
calculating ...............................146
definition .................................145
driving with a heavy load ......145
location ....................................145
GVWR (Gross Vehicle Weight
Rating) .......................................145
calculating .......................145–146
definition .................................145
driving with a heavy load ......145
location ....................................145
H
Hazard flashers .........................175
Headlamps ...................................38
aiming ........................................40
autolamp system .......................38
daytime running lights .............39
flash to pass ..............................40
high beam .................................39
replacing bulbs ...................43–44
turning on and off ....................38
Heating
heating and air conditioning
system .................................35–36
Hood ..........................................216
I
Ignition ...............................110, 260
2003 F250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA English(fus)
Index
276