JEEP GRAND CHEROKEE 2011 WK2 / 4.G Owners Manual

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 trailer tongue
weight. The total load must be limited so that you do not
exceed the GVWR. Refer to “Vehicle Loading/Vehicle
Certification Label” in “Starting and Operating” for
further information.
Gross Trailer Weight (GTW)
The GTW is the weight of the trailer plus the weight of all
cargo, consumables and equipment (permanent or tem-
porary) loaded in or on the trailer in itsloaded and
ready for operation condition.
The recommended 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.
WARNING!
If the gross trailer weight is 3,500 lbs (1 587 kg) or
more, it is mandatory to use a weight-distributing
hitch to ensure stable handling of your vehicle. If
you use a standard weight-carrying hitch, you could
lose control of your vehicle and cause a collision.
Gross Combination Weight Rating (GCWR)
The GCWR is the total permissible weight of your vehicle
and trailer when weighed in combination.
NOTE: The GCWR rating includes 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
5
STARTING AND OPERATING 439

rear GAWR. Refer to “Vehicle Loading/Vehicle Certifica-
tion Label” in “Starting and Operating” for further
information.
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 a collision.
Trailer Tongue Weight (TW)
The TW is 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.
Frontal Area
The frontal area is the maximum height multiplied by the
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 are commonly used to tow small- and medium-
sized trailers.
Weight-Distributing Hitch
A weight-distributing hitch system works by applying
leverage 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’ direc-
tions, it provides for a more level ride, offering more
consistent steering and brake control, thereby enhancing
towing safety. The addition of a friction/hydraulic sway
control also dampens sway caused by traffic and cross-
winds, and contributes positively to tow vehicle and
440 STARTING AND OPERATING

trailer stability. Trailer sway control and a weight-
distributing (load equalizing) hitch are recommended for
heavier trailer 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, and brak-
ing performance, and could result in a collision.
•Weight-distributing hitch systems may not be
compatible with Surge Brake Couplers. Consult
with your hitch and trailer manufacturer or a
reputable Recreational Vehicle dealer for addi-
tional information.Without Weight-Distributing Hitch (Incorrect)
5
STARTING AND OPERATING 441

With Weight-Distributing Hitch (Correct)Improper Adjustment of Weight-Distributing Hitch(Incorrect)
442 STARTING AND OPERATING

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 authorized
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 DefinitionsClass Max. Trailer Hitch Industry Standards
Class I - Light Duty 2,000 lbs (907 kg)
Class II - Medium
Duty 3,500 lbs (1 587 kg)
Class III - Heavy Duty 5,000 lbs (2 268 kg)
Class IV - Extra
Heavy Duty 10,000 lbs (4 540 kg)
Refer to the “Trailer Towing Weights (Maximum
Trailer Weight Ratings)” chart for the Maximum
Gross Trailer Weight (GTW) towable for your given
drivetrain.
All trailer hitches should be professionally installed on
your vehicle.
5
STARTING AND OPERATING 443

Trailer Towing Weights (Maximum Trailer Weight Ratings)
The following chart provides the maximum trailer weight ratings towable for your given drivetrain.
Engine/Model Model GCWR (Gross Com-bined Wt. Rating)Frontal Area Max. GTW
(Gross Trailer Wt.) Max. Trailer
Tongue Wt. (See Note)
3.6L 4x2 8,900 lbs (4 037 kg) 40 sq ft (3.72 sq m) 5,000 lbs (2 268 kg) 500 lbs (227 kg)
3.6L 4x4 8,900 lbs (4 037 kg) 40 sq ft (3.72 sq m) 5,000 lbs (2 268 kg) 500 lbs (227 kg)
5.7L 4x2 13,100 lbs (5 942 kg) 60 sq ft (5.57 sq m) 7,400 lbs (3 357 kg) 740 lbs (336 kg)
5.7L 4x4 13,100 lbs (5 942 kg) 60 sq ft (5.57 sq m) 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 Tire and Loading Information placard. Refer to
“Tire Safety Information” in “Starting and Operating” for further information. The addition of passengers
and cargo may require reducing trailer tongue load and Gross Trailer Weight (GTW). Redistributing cargo
(to the trailer) may be necessary to avoid exceeding Rear Gross Axle Weight Rating (GAWR) of 3,700 lbs
(1 678 kg).
444 STARTING AND OPERATING

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 collisions. 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:
•The trailer tongue weight of the trailer.
•The weight of any other type of cargo or equipment
put in or on your vehicle.
•The weight of the driver and all passengers.
5
STARTING AND OPERATING 445

NOTE:Remember that everything put into or on the
trailer adds to the load on your vehicle. Also, additional
factory-installed options, or authorized dealer-installed
options, must be considered as part of the total load on
your vehicle. Refer to “Tire Safety Information/Tire and
Loading Information Placard” in “Starting and Operat-
ing” for further information.
Towing Requirements
To promote proper break-in of your new vehicle drive-
train components, the following guidelines are recom-
mended.
CAUTION!
•Do not tow a trailer at all during the first 500 miles
(805 km) the new vehicle is driven. The engine,
axle or other parts could be damaged.
(Continued)
CAUTION! (Continued)
•Then, during the first 500 miles (805 km) that a
trailer is towed, do not drive over 50 mph
(80 km/h) and do not make starts at full throttle.
This helps the engine and other parts of the
vehicle wear in at the heavier loads.
Perform the maintenance listed in the “Maintenance
Schedule.” Refer to “Maintenance Schedule” for the
proper maintenance intervals. When towing a trailer,
never exceed the GAWR or GCWR ratings.
WARNING!
Improper towing can lead to a collision. Follow these
guidelines to make your trailer towing as safe as
possible: (Continued)
446 STARTING AND OPERATING

WARNING! (Continued)
•Make certain that the load is secured in the trailer
and will not shift during travel. When trailering
cargo that is not fully secured, dynamic load shifts
can occur that may be difficult for the driver to
control. You could lose control of your vehicle and
have a collision.
•When hauling cargo or towing a trailer, do not
overload your vehicle or trailer. Overloading can
cause a loss of control, poor performance or dam-
age to brakes, axle, engine, transmission, steering,
suspension, chassis structure or tires.
•Safety chains must always be used between your
vehicle and trailer. Always connect the chains to
the hook retainers of the vehicle hitch. Cross the
chains under the trailer tongue and allow enough
slack for turning corners.(Continued)
WARNING! (Continued)
•Vehicles with trailers should not be parked on a
grade. When parking, apply the parking brake on
the tow vehicle. Put the tow vehicle transmission
in PARK. For four-wheel drive vehicles, make sure
the transfer case is not in NEUTRAL. Always,
block orchockthe trailer wheels.
•GCWR must not be exceeded.
•Total weight must be distributed between the tow
vehicle and the trailer such that the following four
ratings are not exceeded:
1. GVWR
2. GTW
3. GAWR
4. Trailer tongue weight rating for the trailer hitch
utilized (This requirement may limit the ability to
always achieve the 10% to 15% range of tongue
weight as a percentage of total trailer weight).5
STARTING AND OPERATING 447

Towing Requirements – Tires

Do not attempt to tow a trailer while using a compact
spare tire.
Proper tire inflation pressures are essential to the safe
and satisfactory operation of your vehicle. Refer to
“Tires – General Information” in “Starting and Oper-
ating” for proper tire inflation procedures.
Check the trailer tires for proper tire inflation pres-
sures before trailer usage.
Check for signs of tire wear or visible tire damage
before towing a trailer. Refer to “Tires – General
Information” in “Starting and Operating” for proper
inspection procedure.
When replacing tires, refer to “Tires – General Infor-
mation” in “Starting and Operating” for proper tire replacement procedures. Replacing tires with a higher
load carrying capacity will not increase the vehicle’s
GVWR and GAWR limits.
Towing Requirements – Trailer Brakes

Do
not interconnect the hydraulic brake system or
vacuum system of your vehicle with that of the trailer.
This could cause inadequate braking and possible
personal injury.
An electronically-actuated trailer brake controller is
required when towing a trailer with electronically-
actuated brakes. When towing a trailer equipped with
a hydraulic surge-actuated brake system, an electronic
brake controller is not required.
Trailer brakes are recommended for trailers over
1,000 lbs (454 kg), and required for trailers in excess of
2,000 lbs (907 kg).
448 STARTING AND OPERATING