
Calculating the load your vehicle can carry/tow
1.
Use the appropriate maximum gross combined weight rating (GCWR)
chart to find the maximum GCWR for your type engine and rear axle ratio.
2. Weigh your vehicle as you customarily operate the vehicle without
cargo. To obtain correct weights, try taking your vehicle to a shipping
company or an inspection station for trucks.
3. Subtract your loaded vehicle weight from the maximum GCWR on the
following charts. This is the maximum combined cargo and trailer weight
your vehicle can carry/tow and must fall below the maximum shown
under maximum trailer weight on the chart. Refer to the definition of
Maximum Trailer Weight below Vehicle Loading in this chapter to
determine the maximum trailer weight permitted for a loaded vehicle.
Vehicle Loading – with and without a trailer
This section will guide you in the proper loading of your vehicle and/or
trailer, to keep your loaded vehicle weight within its design rating
capability, with or without a trailer. Properly loading your vehicle will
provide maximum return of vehicle design performance. Before loading
your vehicle, familiarize yourself with the following terms for determining
your vehicle’s weight ratings, with or without a trailer, from the vehicle’s
Safety Certification Label and Tire and Load Information Label:
Base Curb Weight–is the weight of the vehicle including a full tank of
fuel and all standard equipment. It does not include passengers, cargo, or
optional equipment.
Vehicle Curb Weight–is the weight of your new vehicle when you
picked it up from your dealer plus any aftermarket equipment.
Cargo Weight–includes all weight added to the Base Curb Weight,
including cargo and optional equipment. When towing, trailer tongue load
or king pin weight is also part of cargo weight.
GAW (Gross Axle Weight)–is the total weight placed on each axle
(front and rear)–including vehicle curb weight and all payload.
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4. Install a new air filter element, ensuring the arrow on the top half of
the air filter housing lines up with the notch on the bottom half of air
filter housing. Be careful not to crimp the filter element edges between
the air filter housing. This could cause filter damage and allow
unmetered air to enter the engine if not properly seated.
5. Replace the two halves of the air filter housing and secure the clamp.
INFORMATION ABOUT UNIFORM TIRE QUALITY GRADING
New vehicles are fitted with tires that
have a rating on them called Tire
Quality Grades. The Quality grades
can be found where applicable on the
tire sidewall between tread shoulder
and maximum section width. For
example:
•Treadwear 200 Traction AA Temperature A
These Tire Quality Grades are determined by standards that the United
States Department of Transportation has set.
Tire Quality Grades apply to new pneumatic tires for use on passenger
cars. They do not apply to deep tread, winter-type snow tires,
space-saver or temporary use spare tires, tires with nominal rim
diameters of 10 to 12 inches or limited production tires as defined in
Title 49 Code of Federal Regulations Part 575.104(c)(2).
U.S. Department of Transportation-Tire quality grades:The U.S.
Department of Transportation requires Ford to give you the following
information about tire grades exactly as the government has written it.
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 1/2) times as well on the government course as a tire
graded 100. The relative performance of tires depends upon the actual
conditions of their use, however, and may depart significantly from the
norm due to variations in driving habits, service practices, and
differences in road characteristics and climate.
Traction AA A B C
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
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![FORD F SERIES MOTORHOME AND COMMERCIAL CHASSIS 2004 11.G Owners Manual •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 no FORD F SERIES MOTORHOME AND COMMERCIAL CHASSIS 2004 11.G Owners Manual •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 no](/manual-img/11/5002/w960_5002-97.png)
•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.
•B-pillar:The structural member at the side of the vehicle behind the
front door.
•Bead area of the tire:Area of the tire next to the rim.
•Sidewall of the tire:Area between the bead area and the tread.
•Tread area of the tire:Area of the perimeter of the tire that
contacts the road when mounted on the vehicle.
•Rim:The metal support (wheel) for a tire or a tire and tube assembly
upon which the tire beads are seated.
INFORMATION CONTAINED ON THE TIRE SIDEWALL
Federal law requires tire manufacturers to place standardized information
on the sidewall of all tires. This information identifies and describes the
fundamental characteristics of the tire and also provides a tire identification
number for safety standard certification and in case of a recall.
Information on“P”type tires
P215/65R15 95H is an example of a
tire size, load index and speed
rating. The definitions of these
items are listed below. (Note that
the tire size, load index and speed
rating for your vehicle may be
different than this example.)
1.P:Indicates a tire, designated by
the Tire and Rim Association
(T&RA), that maybe used for
service on cars, SUVs, minivans and
light trucks.
Note:If your tire size does not
begin with a letter this may mean it
is designated by either ETRTO
(European Tire and Rim Technical Organization) or JATMA (Japan Tire
Manufacturing Association).
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2.215:Indicates the nominal width of the tire in millimeters from
sidewall edge to sidewall edge. In general, the larger the number, the
wider the tire.
3.65:Indicates the aspect ratio which gives the tire’s ratio of height to
width.
4.R:Indicates a“radial”type tire.
5.15:Indicates the wheel or rim diameter in inches. If you change your
wheel size, you will have to purchase new tires to match the new wheel
diameter.
6.95:Indicates the tire’s load index. It is an index that relates to how
much weight a tire can carry. You may find this information in your
owner’s guide. If not, contact a local tire dealer.
Note:You may not find this information on all tires because it is not
required by federal law.
7.H:Indicates the tire’s speed rating. The speed rating denotes the
speed at which a tire is designed to be driven for extended periods of
time under a standard condition of load and inflation pressure. The tires
on your vehicle may operate at different conditions for load and inflation
pressure. These speed ratings may need to be adjusted for the difference
in conditions. The ratings range from 159 km/h (99 mph) to 299 km/h
(186 mph). These ratings are listed in the following chart.
Note:You may not find this information on all tires because it is not
required by federal law.
Letter rating Speed rating - km/h (mph)
Q 159 km/h (99 mph)
R 171 km/h (106 mph)
S 180 km/h (112 mph)
T 190 km/h (118 mph)
U 200 km/h (124 mph)
H 210 km/h (130 mph)
V 240 km/h (149 mph)
W 270 km/h (168 mph)
Y 299 km/h (186 mph)
Note:For tires with a maximum speed capability over 240 km/h (149
mph), tire manufacturers sometimes use the letters ZR. For those with
a maximum speed capability over 299 km/h (186 mph), tire letters ZR.
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13.Maximum Permissible Inflation Pressure:Tire manufactures
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 certification label which is
located on the structure by the trailing edge of the driver’s door or the
edge of the driver’s door. The cold inflation pressure should never be set
lower than the recommended pressure on the label.
Note:You may not find this information on all tires because it is not
required by federal law.
The tire suppliers may have additional markings, notes or warnings such
as standard load, radial tubeless, etc.
Additional information contained on the tire sidewall for“LT”type
tires
“LT”type tires have some additional
information than those of“P”type
tires; these differences are
described below:
1.LT:Indicates a tire, designated by
the Tire and Rim Association
(T&RA), that is intended for service
on light trucks.
2.Load Range/Load Inflation
Limits:Indicates the tires
load-carrying capabilities and its
inflation limits.
3.Maximum Load Dual kg (lbs.)
at kPa (psi) cold:Indicates the
maximum load and tire pressure
when the tire is used as a dual; a
dual is defined as when four tires are put on the rear axle (a total of six
or more tires on the vehicle).
4.Maximum Load Single kg (lbs.) at kPa (psi) cold:Indicates the
maximum load and tire pressure when the tire is used as a single; a
single is defined as when two tires (total) are put on the rear axle.
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Information on“T”type tires
T145/80D16 is an example of a tire
size.
Note:The temporary tire size for
your vehicle may be different than
this example.
1.T:Indicates a type of tire,
designated by the Tire and Rim
Association (T&RA), that is
intended for temporary service on
cars, SUVs, minivans and light
trucks.
2.145:Indicates the nominal width
of the tire in millimeters from
sidewall edge to sidewall edge. In
general, the larger the number, the
wider the tire.
3.80:Indicates the aspect ratio
which gives the tires ratio of height to width. Numbers of 70 or lower
indicate a short sidewall.
4.D:Indicates a“diagonal”type tire.
R:Indicates a“radial”type tire.
5.16:Indicates the wheel or rim diameter in inches. If you change your
wheel size, you will have to purchase new tires to match the new wheel
diameter.
Location of the tire label
You will find a tire label containing tire inflation pressure by tire size and
other important information located on the B-Pillar or the driver’s door.
TIRE CARE
Improper or inadequate vehicle maintenance can also cause tires to wear
abnormally. Here are some of the important maintenance items
SPARETIRE
TEMPORARYUSEONLY
INFLATETO60P.S.I.T
T145/80D16105M
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Tire inflation pressure
Use a tire gauge to check the tire inflation pressure at least monthly
(check the tire inflation pressure in the spare tire every 6 months) and
before long trips. You are strongly urged to buy a reliable tire pressure
gauge, as automatic service station gauges may be inaccurate. Ford
recommends the use of a digital or dial type tire pressure gauge rather
than a stick type of tire pressure gauge.
Use the recommended cold inflation pressure for optimum tire
performance and wear. Under-inflation or over-inflation may cause
uneven treadwear patterns.
Under-inflation is the most common cause of tire failures and
may result in severe tire cracking, tread separation orblowout,
with unexpected loss of vehicle control and increased risk of injury.
Under-inflation increases sidewall flexing and rolling resistance,
resulting in heat buildup and internal damage to the tire. It also may
result in unnecessary tire stress, irregular wear, loss of vehicle control
and accidents. A tire can lose up to half of its air pressure and not
appear to be flat!
When weather temperature changes occur, tire inflation pressures also
change. A 10 degree temperature change causes a corresponding drop of
7 kPa (1 psi) in inflation pressure. Check your tire pressures frequently
and adjust them to the proper pressure which can be found on the tire
label or certification label.
If checking tire pressure when the tire is hot, (i.e. driven more than 1.6
km [1mile]), never“bleed”or reduce air pressure. The tires are hot from
driving and it is normal for pressures to increase above recommended
cold pressures. A hot tire at or below recommended cold inflation
pressure could be significantly under-inflated.
To check the pressure in your tire(s):
1. Make sure the tires are cool, meaning they are not hot from driving
even a mile.
Note:If you have to drive a distance to get air for your tire(s), check
and record the tire pressure first and add the appropriate air pressure
when you get to the pump. It is normal for tires to heat up and the air
pressure inside to go up as you drive. Never“bleed”or reduce air
pressure when tires are hot.
2. Remove the cap from the valve on one tire, then firmly press the tire
gauge onto the valve.
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3. Add air to reach the recommended air pressure
Note:If you overfill the tire, release air by pushing on the metal stem in
the center of the valve. Then recheck the pressure with your tire gauge.
4. Replace the valve cap.
5. Repeat this procedure for each tire, including the spare.
Note:Some spare tires require higher inflation pressure than the other
tires.
6. Visually inspect the tires to make sure there are no nails or other
objects embedded that could poke a hole in the tire and cause an air
leak.
7. Check the sidewalls to make sure there are no gouges, cuts, bulges or
other irregularities.
Tire inflation information
All tires with Steel Carcass Plies (if equipped):
This type of tire utilizes steel cords in the sidewalls. As such, they
cannot be treated like normal light truck tires. Tire service, including
adjusting tire pressure, must be performed by personnel trained,
supervised and equipped according to Federal Occupational Safety and
Health Administration (OSHA) regulations. For example, during any
procedure involving tire inflation, the technician or individual must
utilize a remote inflation device, and insure that all persons are clear of
the trajectory area.
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