2008 FORD F350 tire pressure

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.
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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.
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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)
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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).
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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.
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3. Attach the trailer to the vehicle and adjust the hitch equalizers so that
the front bumper height is within12” (13 mm) of the reference point.
After proper adjustment, the rear bumper should be no higher than in
Step 2.
Note:Adjusting a weight distributing hitch so the rear bumper of the
vehicle is higher than it was unloaded will defeat the function of the
weight distributing hitch and may cause unpredictable handling.
Safety chains
Always connect the trailer’s safety chains to the frame or hook retainers
of the vehicle hitch. To connect the trailer’s safety chains, cross the
chains under the trailer tongue and allow slack for turning corners.
If you use a rental trailer, follow the instructions that the rental agency
gives to you.
Do not attach safety chains to the bumper.
Trailer brakes
Electric brakes and manual, automatic or surge-type trailer brakes are
safe if installed properly and adjusted to the manufacturer’s
specifications. The trailer brakes must meet local and Federal
regulations.
If you own a trailer with a hydraulic brake system, do not
connect the trailer’s hydraulic brake system directly to your
vehicle’s brake system. The vehicle’s brake system is only designed to
carry the appropriate amount of brake fluid for the vehicle alone.
Connecting a hydraulic trailer braking system could adversely affect
your vehicle’s braking performance.
The braking system of the tow vehicle is rated for operation at the
GVWR not GCWR.
Integrated trailer brake controller (if equipped)
Your vehicle may be equipped with a fully integrated electronic Trailer
Brake Controller (TBC). When used properly, the TBC helps ensure
smooth and effective trailer braking by powering the trailer’s electric
brakes with a proportional output based on the towing vehicle’s brake
pressure.
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Backing up
•Practice backing up, particularly if you are a novice. Turn the steering
wheel to the right to move the trailer’s rear end to the right.
•Sharp steering movements may cause the trailer to jackknife or go out
of control.
Tires
•All trailer tires should be of the same size, and construction.
•Select tires that meet the trailer loading requirements.
•Always check tow vehicle and trailer tire pressure before towing.
Launching or retrieving a boat
When backing down a ramp during boat launching or retrieval,
•Do not allow the static water level to rise above the bottom edge of
the rear bumper.
•Do not allow waves to break higher than 6 inches (15 cm) above the
bottom edge of the rear bumper.
•Disconnect the trailer tow electrical connector to prevent blown fuses
caused by water entering into your trailer’s electrical wiring.
Exceeding these limits may allow water to enter critical vehicle
components, adversely affecting driveability, emissions and reliability.
Replace front and rear axle lubricants any time the axles have been
submerged in water. Axle lubricant quantities are not to be checked
unless a leak is suspected.
RECREATIONAL TOWING
Follow these guidelines if you have a need for recreational (RV) towing.
An example of recreational towing would be towing your vehicle behind
a motorhome. These guidelines are designed to ensure that your
transmission is not damaged.
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Do not rock the vehicle for more than a few minutes or damage to
the transmission and tires may occur or the engine may overheat.
Do not spin the wheels at over 35 mph (56 km/h). The tires may
fail and injure a passenger or bystander.
Refer toTransmission fluid temperature gaugein theInstrument
Clusterchapter for transmission fluid temperature information.
Emergency maneuvers
•In an unavoidable emergency situation where a sudden sharp turn
must be made, remember to avoid “over-driving” your vehicle, i.e.,
turn the steering wheel only as rapidly and as far as required to avoid
the emergency. Excessive steering will result in less vehicle control,
not more. Additionally, smooth variations of the accelerator and/or
brake pedal pressure should be utilized if changes in vehicle speed are
called for. Avoid abrupt steering, acceleration or braking which could
result in an increased risk of loss of vehicle control, vehicle rollover
and/or personal injury. Use all available road surface to return the
vehicle to a safe direction of travel.
•In the event of an emergency stop, avoid skidding the tires and do not
attempt any sharp steering wheel movements.
Vehicles with a higher center of gravity such as utility and
four-wheel drive vehicles handle differently than vehicles with a
lower center of gravity. Utility and four-wheel drive vehicles arenot
designed for cornering at speeds as high as passenger cars any more
than low-slung sports cars are designed to perform satisfactorily under
off-road conditions. Avoid sharp turns, excessive speed and abrupt
maneuvers in these vehicles. Failure to drive cautiously could result in
an increased risk of loss of vehicle control, vehicle rollover, personal
injury and death.
•If the vehicle goes from one type of surface to another (i.e., from
concrete to gravel) there will be a change in the way the vehicle
responds to a maneuver (steering, acceleration or braking). Again,
avoid these abrupt inputs.
Parking
On some 4WD vehicles, when the transfer case is in the N (Neutral)
position, the engine and transmission are disconnected from the rest of
the driveline. Therefore, the vehicle is free to roll even if the automatic
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