PRINCIPLES OF OPERATION
WARNING:Vehicle modifications involving braking system,
aftermarket roof racks, suspension, steering system, tire
construction or wheel and tire size may change the handling
characteristics of the vehicle and may adversely affect the performance
of the AdvanceTrac® system. In addition, installing any stereo
loudspeakers may interfere with and adversely affect the AdvanceTrac®
system. Install any aftermarket stereo loudspeaker as far as possible
from the front center console, the tunnel, and the front seats in order
to minimize the risk of interfering with the AdvanceTrac® sensors.
Reducing the effectiveness of the AdvanceTrac® system could lead to
an increased risk of loss of vehicle control, vehicle rollover, personal
injury and death.
WARNING: Remember that even advanced technology cannot
defy the laws of physics. It’s always possible to lose control of a
vehicle due to inappropriate driver input for the conditions. Aggressive
driving on any road condition can cause you to lose control of your
vehicle increasing the risk of personal injury or property damage.
Activation of the AdvanceTrac® system is an indication that at least
some of the tires have exceeded their ability to grip the road; this could
reduce the operator’s ability to control the vehicle potentially resulting
in a loss of vehicle control, vehicle rollover, personal injury and death. If
your AdvanceTrac® system activates, SLOW DOWN.
The AdvanceTrac® with Roll Stability Control™ system helps you keep
control of your vehicle when on a slippery surface. The electronic
stability control portion of the system helps avoid skids and lateral slides
and roll stability control helps avoid a vehicle rollover. The traction
control system helps avoid drive wheel spin and loss of traction. See the
Traction Control chapter for details on traction control system
operation.
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•If your vehicle is equipped with Continuous Controlled Damping
Suspension (CCD Suspension), you can select NORMAL or SPORT
drive control modes for better experience while towing a trailer. See
the Information Displays chapter for details on selecting driving
modes.
• If you are towing a trailer frequently in hot weather, hilly conditions,
at the gross combined weight rating (or any combination of these
factors), consider refilling your rear axle with synthetic gear lubricant
(if the axle is not already filled with it). See the Capacities and
Specifications chapter for the lubricant specification.
• Allow more distance for stopping with a trailer attached. Anticipate
stops and brake gradually.
• Avoid parking on a grade. However, if you must park on a grade:
1. Turn the steering wheel to point your vehicle tires away from traffic flow.
2. Set your vehicle parking brake.
3. Place the automatic transmission in position P.
4. Place wheel chocks in front and back of the trailer wheels. (Chocks not included with vehicle.)
Your vehicle may be equipped with a temporary or conventional spare
tire. A “temporary” spare tire is different in size (diameter or width),
tread-type (All-Season or All-Terrain) or is from a different manufacturer
than the road tires on your vehicle. Consult information on the tire label
or Safety Compliance label for limitations when using.
Launching or Retrieving a Boat or Personal Watercraft (PWC)
Note: Disconnect the wiring to the trailer beforebacking the trailer into
the water.
Note: Reconnect the wiring to the trailer afterremoving the trailer from
the water.
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 centimeters)
above the bottom edge of the rear bumper.
Exceeding these limits may allow water to enter vehicle components:
• Causing internal damage to the components.
• Affecting driveability, emissions, and reliability.
Replace the rear axle lubricant anytime the rear axle submerges in
water. Water may have contaminated the rear axle lubricant, which does
not normally require checking or changing unless it is leaking or other
axle repair is required.
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BREAKING-IN
You need to break in new tires for approximately 300 miles
(480 kilometers). During this time, your vehicle may exhibit some unique
driving characteristics. Avoid driving too fast during the first 1000 miles
(1600 kilometers). Vary your speed frequently and change up through
the gears early. Do not labor the engine. Do not tow during the first
1000 miles (1600 kilometers).
ECONOMICAL DRIVING
Fuel economy is affected by several things, such as how you drive, the
conditions you drive under and how you maintain your vehicle.
There are some things to keep in mind that may improve your fuel
economy:
•Accelerate and slow down in a smooth, moderate fashion.
• Drive at steady speeds without stopping.
• Anticipate stops; slowing down may eliminate the need to stop.
• Combine errands and minimize stop-and-go driving.
• Close the windows for high-speed driving.
• Drive at reasonable speeds (traveling at 55 mph [88 km/h] uses 15%
less fuel than traveling at 65 mph [105 km/h]).
• Keep the tires properly inflated and use only the recommended size.
• Use the recommended engine oil.
• Perform all regularly scheduled maintenance.
There are also some things you may not want to do because they may
reduce your fuel economy:
• Sudden or hard accelerations.
• Rev the engine before turning it off.
• Idle for periods longer than one minute.
• Warm up your vehicle on cold mornings.
• Use the air conditioner or front defroster.
• Use the speed control in hilly terrain.
• Rest your foot on the brake pedal while driving.
• Drive a heavily loaded vehicle or tow a trailer.
• Carry unnecessary weight (approximately 1 mpg [0.4 km/L] is lost for
every 400 pounds [180 kilograms] of weight carried).
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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 1
1 2times 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
WARNING:The traction grade assigned to this tire is based on
straight-ahead braking traction tests, and does not include
acceleration, cornering, hydroplaning or peak traction characteristics.
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 A B C
WARNING: The temperature grade for this tire is established for
a tire that is properly inflated and not overloaded. Excessive
speed, underinflation, or excessive loading, either separately or in
combination, can cause heat buildup and possible tire failure.
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. Sustained high temperature can cause the material of the tire
to degenerate and reduce tire life, and excessive temperature can lead to
sudden tire failure. The grade C corresponds to a level of performance
which all passenger car tires must meet under the Federal Motor Vehicle
Safety Standard No. 139. Grades B and A represent higher levels of
performance on the laboratory test wheel than the minimum required by
law.
Glossary of Tire Terminology
• Tire label: A label showing the OE (Original Equipment) tire sizes,
recommended inflation pressure and the maximum weight the vehicle
can carry.
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•Tire Identification Number (TIN): A number on the sidewall of
each tire providing information about the tire brand and
manufacturing plant, tire size and date of manufacture. Also referred
to as DOT code.
• Inflation pressure: A measure of the amount of air in a tire.
• Standard load: A class of P-metric or Metric tires designed to carry a
maximum load at set pressure. For example: For P-metric tires 35 psi
(2.4 bar) or 36 (2.5 bar) depending on tire size and for Metric tires
36 psi (2.5 bar). Increasing the inflation pressure beyond this pressure
will not increase the tire capability.
• Extra load: A class of P-metric or Metric tires designed to carry a
heavier maximum load at 42 psi (2.9 bar). Increasing the inflation
pressure beyond this pressure will not increase the tire’s load-carrying
capability.
• kPa: KiloPascal, a metric unit of air pressure.
• PSI: Pounds per square inch, a standard unit of air pressure.
• Cold tire pressure: The tire pressure when the vehicle has been
stationary and out of direct sunlight for an hour or more and prior to
the vehicle being driven for 1 mile (1.6 kilometers).
• Recommended inflation pressure: The cold inflation pressure found
on the Safety Compliance Certification Label (affixed to either the
door hinge pillar, door-latch post, or the door edge that meets the
door-latch post, next to the driver’s seating position) or Tire Label
located on the B-Pillar or the edge of the driver’s door.
• 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
Both U.S. and Canada Federal regulations require 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 U.S. DOT Tire Identification Number for
safety standard certification and in case of a recall.
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Information on P Type TiresP215/65R15 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 from this example.)
A. P: Indicates a tire, designated by the Tire and Rim Association, that
may be used for service on cars, sport utility vehicles, minivans and light
trucks.
Note: If your tire size does not begin with a letter, this may mean it is
designated by either the European Tire and Rim Technical Organization
or the Japan Tire Manufacturing Association.
B. 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.
C. 65: Indicates the aspect ratio which gives the tire’s ratio of height to
width.
D. R: Indicates a radial type tire.
E. 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.
F. 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 manual. 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.
H
I
J
KL
M
A
B
CDEFG
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G.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 81 mph (130 km/h) to 186 mph
(299 km/h). 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 - mph (km/h)
M 81 (130)
N 87 (140)
Q 99 (159)
R 106 (171)
S 112 (180)
T 118 (190)
U 124 (200)
H 130 (210)
V 149 (240)
W 168 (270)
Y 186 (299 )
Note: For tires with a maximum speed capability over 149 mph
(240 km/h), tire manufacturers sometimes use the letters ZR. For
those with a maximum speed capability over 186 mph (299 km/h), tire
manufacturers always use the letters ZR.
H. U.S. DOT Tire Identification Number (TIN): This begins with the
letters DOT and indicates that the tire meets all federal standards. The
next two numbers or letters are the plant code designating where it was
manufactured, the next two are the tire size code and the last four
numbers represent the week and year the tire was built. For example,
the numbers 317 mean the 31st week of 1997. After 2000 the numbers
go to four digits. For example, 2501 means the 25th week of 2001. The
numbers in between are identification codes used for traceability. This
information is used to contact customers if a tire defect requires a recall.
I. M+S or M/S: Mud and Snow, or
AT: All Terrain, or
AS: All Season.
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Information on T Type TiresT type tires have some additional
information beyond those of P type
tires. These differences are
described below.
T145/80D16 is an example of a tire
size.
Note:The temporary tire size for
your vehicle may be different from
this example. Tire Quality Grades
do not apply to this type of tire.
A. T:Indicates a type of tire, designated by the Tire and Rim
Association, that is intended for temporary service on cars, sport-utility
vehicles, minivans and light trucks.
B. 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.
C. 80: Indicates the aspect ratio, which gives the tire’s ratio of height to
width. Numbers of 70 or lower indicate a short sidewall.
D. D: Indicates a diagonal type tire. R:Indicates a radial type tire.
E. 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 edge of
the driver’s door. See the payload description and graphic in the Load
Carrying chapter.
A
BCDE
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