2008 FORD F250 warning

10.Tire Ply Composition and Material Used:Indicates the number of
plies or the number of layers of rubber-coated fabric in the tire tread and
sidewall. Tire manufacturers also must indicate the ply materials in the
tire and the sidewall, which include steel, nylon, polyester, and others.
11.Maximum Load:Indicates the maximum load in kilograms and
pounds that can be carried by the tire. Refer to the Tire Label or Safety
Compliance Certification Label, which is located on the B-Pillar or the
edge of the driver’s door, for the correct tire pressure for your vehicle.
12.Treadwear, Traction and Temperature Grades
•Treadwear:The treadwear grade is a comparative rating based on the
wear rate of the tire when tested under controlled conditions on a
specified government test course. For example, a tire graded 150
would wear one and one-half (1
12) times as well on the government
course as a tire graded 100.
•Traction:The traction grades, from highest to lowest are AA, A, B,
and C. The grades represent the tire’s ability to stop on wet pavement
as measured under controlled conditions on specified government test
surfaces of asphalt and concrete. A tire marked C may have poor
traction performance.
•Temperature: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.
13.Maximum Permissible Inflation Pressure:Indicates the tire
manufacturers’ maximum permissible pressure and/or the pressure at
which the maximum load can be carried by the tire. This pressure is
normally higher than the manufacturer’s recommended cold inflation
pressure which can be found on either the Tire Label or Safety
Compliance Certification Label which is located on the B-Pillar or the
edge of the driver’s door. The cold inflation pressure should never be set
lower than the recommended pressure on the vehicle label.
The tire suppliers may have additional markings, notes or warnings such
as standard load, radial tubeless, etc.
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
221

Understanding your Tire Pressure Monitoring System (TPMS)
The Tire Pressure Monitoring System measures pressure in your four
road tires and sends the tire pressure readings to your vehicle. The Low
Tire Warning Lamp will turn ON if the tire pressure is significantly low.
Once the light is illuminated, your tires are under inflated and need to be
inflated to the manufacturer’s recommended tire pressure. Even if the
light turns ON and a short time later turns OFF, your tire pressure still
needs to be checked. Visit www.checkmytires.org for additional
information.
When your temporary spare tire is installed
When one of your road tires needs to be replaced with the temporary
spare, the TPMS system will continue to identify an issue to remind you
that the damaged road wheel/tire needs to be repaired and put back on
your vehicle.
To restore the full functionality of the Tire Pressure Monitoring System,
have the damaged road wheel/tire repaired and remounted on your
vehicle. For additional information, refer toChanging tires with TPMS
in this section.
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
226

When you believe your system is not operating properly
The main function of the Tire Pressure Monitoring System is to warn you
when your tires need air. It can also warn you in the event the system is no
longer capable of functioning as intended. Please refer to the following
chart for information concerning your Tire Pressure Monitoring System:
Low Tire Pressure
Warning LightPossible cause Customer Action Required
Solid Warning Light Tire(s)
under-inflated1. Check your tire pressure to
ensure tires are properly
inflated; refer toInflating your
tiresin this chapter.
2. After inflating your tires to
the manufacturer’s
recommended inflation pressure
as shown on the Tire Label
(located on the edge of driver’s
door or the B-Pillar), the
vehicle must be driven for at
least two minutes over 20 mph
(32 km/h) before the light will
turn OFF.
Spare tire in
useYour temporary spare tire is in
use. Repair the damaged road
wheel/tire and reinstall it on the
vehicle to restore system
functionality. For a description
on how the system functions,
refer toWhen your temporary
spare tire is installedin this
section.
TPMS
malfunctionIf your tires are properly
inflated and your spare tire is
not in use and the light remains
ON, have the system inspected
by your authorized dealer.
Tire rotation
without sensor
trainingOn vehicles with different front
and rear tire pressures, the
TPMS system must be retrained
following every tire rotation.
Refer toTire rotationin this
chapter.
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
227

Low Tire Pressure
Warning LightPossible cause Customer Action Required
Flashing Warning
LightSpare tire in
useYour temporary spare tire is in
use. Repair the damaged road
wheel and re-mount it on the
vehicle to restore system
functionality. For a description
of how the system functions
under these conditions, refer to
When your temporary spare
tire is installedin this section.
TPMS
malfunctionIf your tires are properly
inflated and your spare tire is
not in use and the TPMS
warning light still flashes, have
the system inspected by your
authorized dealer.
When inflating your tires
When putting air into your tires (such as at a gas station or in your
garage), the Tire Pressure Monitoring System may not respond
immediately to the air added to your tires.
It may take up to two minutes of driving over 20 mph (32 km/h) for the
light to turn OFF after you have filled your tires to the recommended
inflation pressure.
How temperature affects your tire pressure
The Tire Pressure Monitoring System (TPMS) monitors tire pressure in
each pneumatic tire. While driving in a normal manner, a typical
passenger tire inflation pressure may increase approximately 2 to 4 psi
(14 to 28 kPa) from a cold start situation. If the vehicle is stationary
over night with the outside temperature significantly lower than the
daytime temperature, the tire pressure may decrease approximately 3 psi
(20.7 kPa) for a drop of 30° F (16.6°C) in ambient temperature. This
lower pressure value may be detected by the TPMS as being significantly
lower than the recommended inflation pressure and activate the TPMS
warning for low tire pressure. If the low tire pressure warning light is
ON, visually check each tire to verify that no tire is flat. (If one or more
tires are flat, repair as necessary.) Check air pressure in the road tires. If
any tire is under-inflated, carefully drive the vehicle to the nearest
location where air can be added to the tires. Inflate all the tires to the
recommended inflation pressure.
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
228

TPMS reset procedure (if applicable)
This procedure is only required after tire rotation on vehicles
with different front and rear tire pressures.
To determine if your vehicle requires two different pressures -
one for the front tires and one for the rear tires - refer to the
Safety Compliance Certification Label or Tire Label which is located on
the B-Pillar or the edge of the driver’s door. SeeVehicle Loadingin
this chapter for more information.
Overview
To provide the vehicle’s load carrying capability, some trucks require
different recommended tire pressures in the front tires as compared to
the rear tires. The Tire Pressure Monitoring System (TPMS) equipped on
these vehicles is designed to illuminate the Low Tire Pressure Warning
indicator at two different pressures; one for the front tires and one for
the rear tires. Since tires need to be rotated to provide consistent
performance and maximum tire life, the Tire Pressure Monitoring System
needs to know when the tires are rotated to determine which set of tires
are on the front and which are on the rear. With this information, the
system can detect and properly warn of low tire pressures.
Always perform the TPMS reset procedure after tire rotation. If
the system is not reset, it may not provide a low tire pressure
warning when necessary.
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
229

Rotation, pressure adjustment and TPMS reset example
The following example describes all the major steps involved in rotating
tires on a vehicle with different front and rear tire pressures. It
illustrates that the TPMS reset procedure needs to follow tire rotation
and pressure adjustment to avoid a possible false low tire warning.
Example:
A particular vehicle has the following recommended tire pressures: 50 psi
(345 kPa) front; 80 psi (552 kPa) rear.
Note:For your vehicle’s pressure, refer to the Safety Compliance
Certification Label located on the B-Pillar or the edge of your vehicle’s
driver’s door.
Before tire rotation
Sensor 1: 50 psi
Sensor 2: 50 psi
Sensor 3: 80 psi
Sensor 4: 80 psi
Tire rotation using the
recommended sequence (front
tires at top of diagram)
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
233

Sensor position following tire
rotation
Sensor 1: 50 psi
Sensor 2: 50 psi
Sensor 3: 80 psi
Sensor 4: 80 psi
Pressure adjustment without the
required TPMS reset procedure
Sensor 1: 80 psi
Sensor 2: 80 psi
Sensor 3: 50 psi
Sensor 4: 50 psi
In this situation, the TPMS warning
light will come on.
If the TPMS reset procedure is not performed after tire rotation and air
pressure adjustment, the TPMS telltale may illuminate for a false low tire
pressure condition.
As in this example, the rear tires rotated to the front and properly
inflated to 50 psi (345 kPa) for the front axle would falsely illuminate the
low tire warning indicator as they are still trained for the rear positions
which require 80 psi (552 kPa).
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
234

Rotation, pressure adjustment
and successful completion of the
TPMS reset procedure
Sensor 1: 80 psi
Sensor 2: 80 psi
Sensor 3: 50 psi
Sensor 4: 50 psi
Tire rotation and air pressure
adjustment followed by sensor
resetting will ensure the system is properly programmed for vehicles
with different front and rear tire pressures and reduce the risk of a false
low tire warning.
In this situation, the TPMS warning light will be off.
SNOW TIRES AND CHAINS
Snow tires must be the same size and grade as the tires you
currently have on your vehicle.
Note:Do not use snow chains on front tires of vehicles with 20” wheels
and tires.
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.
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
235