2008 JEEP COMMANDER Owners Manual

Each axle GAWR is determined by the components in the
system with the lowest load carrying capacity (axle,
springs, tires, or wheels). Heavier axles or suspension
components sometimes specified by purchasers for in-
creased durability does not necessarily increase the vehi-
cle's GVWR.
Tire Size
The tire size on the Label represents the actual tire size on
your vehicle. Replacement tires must be equal to the load
capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size
listed.
Inflation Pressure
This is the cold tire inflation pressure for your vehicle for
all loading conditions up to full GAWR.
Curb Weight
The curb weight of a vehicle is defined as the total weight
of the vehicle with all fluids, including vehicle fuel, at full
capacity conditions, and with no occupants or cargo
loaded into the vehicle. The front and rear curb weight
values are determined by weighing your vehicle on a
commercial scale before any occupants or cargo are
added.
Loading
The actual total weight and the weight of the front and
rear of your vehicle at the ground can best be determined
by weighing it when it is loaded and ready for operation.
The entire vehicle should first be weighed on a commer-
cial scale to insure that the GVWR has not been exceeded.
The weight on the front and rear of the vehicle should
then be determined separately to be sure that the load is
properly distributed over front and rear axle. Weighing
the vehicle may show that the GAWR of either the front
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or rear axles has been exceeded but the total load is
within the specified GVWR. If so, weight must be shifted
from front to rear or rear to front as appropriate until the
specified weight limitations are met. Store the heavier
items down low and be sure that the weight is distributed
equally. Stow all loose items securely before driving.
Improper weight distributions can have an adverse effect
on the way your vehicle steers and handles and the way
the brakes operate.
CAUTION!
Do not load your vehicle any heavier than the GVWR
or the maximum front and rear GAWR. If you do,
parts on your vehicle can break, or it can change the
way your vehicle handles. This could cause you to
lose control. Also overloading can shorten the life of
your vehicle.
TRAILER TOWING
In this section you will find safety tips and information
on limits to the type of towing you can reasonably do
with your vehicle. Before towing a trailer carefully re-
view this information to tow your load as efficiently and
safely as possible.
To maintain warranty coverage, follow the requirements
and recommendations in this manual concerning ve-
hicles used for trailer towing.
Common Towing Definitions
The following trailer towing related definitions will assist
you in understanding the following information:
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total allowable weight of your vehicle.
This includes driver, passengers, cargo and tongue
weight. The total load must be limited so that you do not
exceed the GVWR.
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Gross Trailer Weight (GTW)
The gross trailer weight (GTW) is the weight of the trailer
plus the weight of all cargo, consumables and equipment
(permanent or temporary) loaded in or on the trailer in its
9loaded and ready for operation9condition. The recom-
mended way to measure GTW is to put your fully loaded
trailer on a vehicle scale. The entire weight of the trailer
must be supported by the scale.
Gross Combination Weight Rating (GCWR)
The gross combination weight rating (GCWR) is the total
permissible weight of your vehicle and trailer when
weighed in combination. (Note that GCWR ratings in-
clude a 150 lbs (68 kg) allowance for the presence of a
driver).
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum capacity of the front and rear
axles. Distribute the load over the front and rear axles
evenly. Make sure that you do not exceed either front or
rear GAWR.
WARNING!
It is important that you do not exceed the maximum
front or rear GAWR. A dangerous driving condition
can result if either rating is exceeded. You could lose
control of the vehicle and have an accident.
Tongue Weight (TW)
The downward force exerted on the hitch ball by the
trailer. In most cases it should not be less than 10% or
more than 15% of the trailer load. You must consider this
as part of the load on your vehicle.
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Frontal Area
The maximum height and maximum width of the front of
a trailer.
Weight-Carrying Hitch
A weight-carrying hitch supports the trailer tongue
weight, just as if it were luggage located at a hitch ball or
some other connecting point of the vehicle. These kind of
hitches are the most popular on the market today and
they're commonly used to tow small- and medium-sized
trailers.
Weight-Distributing Hitch
A weight-distributing system works by applying lever-
age through spring (load) bars. They are typically used
for heavier loads, to distribute trailer tongue weight to
the tow vehicle's front axle and the trailer axle(s). When
used in accordance with the manufacturers' directions, it
provides for a more level ride, offering more consistent
steering and brake control thereby enhancing towingsafety. The addition of a friction/hydraulic sway control
also dampens sway caused by traffic and crosswinds and
contributes positively to tow vehicle and trailer stability.
Trailer sway control and a weight distributing (load
equalizing) hitch are recommended for heavier Tongue
Weights (TW) and may be required depending on Vehicle
and Trailer configuration/loading to comply with gross
axle weight rating (GAWR) requirements.
WARNING!
An improperly adjusted Weight Distributing Hitch
system may reduce handling, stability, braking per-
formance, and could result in an accident.
Weight Distributing Systems may not be compatible
with Surge Brake Couplers. Consult with your hitch
and trailer manufacturer or a reputable Recreational
Vehicle dealer for additional information.
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Weight Distributing Hitch SystemImproper Adjustment of Weight Distributing System
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Trailer Hitch Classification
Your vehicle may be factory equipped for safe towing of
trailers weighing over 3,500 lbs (1 587 kg) with the
optional Trailer Tow Prep Package. See your dealer for
package content.
The following chart provides the industry standard for
the maximum trailer weight a given trailer hitch class can
tow and should be used to assist you in selecting the
correct trailer hitch for your intended towing condition.
Refer to the Trailer Towing Weights (Maximum Trailer
Weight Ratings) chart for the Max. GTW towable for your
given drivetrain.Trailer Hitch Classification
Class Max. GTW
(Gross Trailer Wt.)
Class I - Light Duty 2,000 lbs (907 kg)
Class II - Medium
Duty3,500 lbs (1 587 kg)
Class III - Heavy Duty 5,000 lbs (2 268 kg)
Class IV - Extra
Heavy Duty10,000 lbs (4 540 kg)
All trailer hitches should be professionally installed on
your vehicle.
Trailer Towing Weights (Maximum Trailer Weight
Ratings)
The following chart provides the maximum trailer
weight ratings towable for your given drivetrain.
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Engine/
TransmissionModel GCWR (Gross Com-
bined Wt. Rating)Frontal Area Max. GTW (Gross
Trailer Wt.)Max. Tongue Wt.
(See Note 1)
3.7L/
Automatic4x2 8,670 lbs (3 933 kg) 40 Sq. Ft (3.72
square meters)3,500 lbs (1 587 kg) 350 lbs (159 kg)
3.7L/
Automatic4x4 8,755 lbs (3 971 kg) 40 Sq. Ft (3.72
square meters)3,500 lbs (1 587 kg) 350 lbs (159 kg)
4.7L/
Automatic4x2 11,665 lbs (5 291 kg) 60 Sq. Ft (5.57
square meters)6,500 lbs (2 948 kg) 650 lbs (295 kg)
4.7L/
Automatic4x4 11,800 lbs (5 352 kg) 60 Sq. Ft (5.57
square meters)6,500 lbs (2 948 kg) 650 lbs (295 kg)
5.7L/
Automatic4x2 12,470 lbs (5 656 kg) 60 Sq. Ft (5.57
square meters)7,200 lbs (3 266 kg) 720 lbs (327 kg)
5.7L/
Automatic4x4 12,620 lbs (5 724 kg) 60 Sq. Ft (5.57
square meters)7,200 lbs (3 266 kg) 720 lbs (327 kg)
Refer to local laws for maximum trailer towing speeds.
NOTE:The trailer tongue weight must be considered as
part of the combined weight of occupants and cargo, and
should never exceed the weight referenced on the Tireand Loading Information placard. Refer to the ªTire±
Safety Informationº section in this manual.
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Trailer and Tongue Weight
Always load a trailer with 60% to 65% of the weight in
the front of the trailer. This places 10% to 15% of the
Gross Trailer Weight (GTW) on the tow hitch of your
vehicle. Loads balanced over the wheels or heavier in the
rear can cause the trailer to swayseverelyside to side
which will cause loss of control of vehicle and trailer.
Failure to load trailers heavier in front is the cause of
many trailer accidents.
Never exceed the maximum tongue weight stamped on
your trailer hitch.
Consider the following items when computing the
weight on the front/rear axles of the vehicle:
²The tongue weight of the trailer.
²The weight of any other type of cargo or equipment
put in or on your vehicle.
²The weight of the driver and all passengers.
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