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Tread Wear Indicators
Tread wear indicators are in the original equipment tires
to help you in determining when your tires should be
replaced.
These indicators are molded into the bottom of the tread
grooves and will appear as bands when the tread depth
becomes 1/16 inch (2 mm). When the indicators appear
in 2 or more adjacent grooves, the tire should be replaced.Many states have laws requiring tire replacement at this
point.
Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressure. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed (see the paragraph on tread
wear indicators). Refer to the Tire and Loading Informa-
tion placard for the size designation of your tire. The
service description and load identification will be found
on the original equipment tire. Failure to use equivalent
replacement tires may adversely affect the safety, han-
dling, and ride of your vehicle. We recommend that you
contact your original equipment or an authorized tire
dealer with any questions you may have on tire specifi-
cations or capability.
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WARNING!
•Do not use a tire, wheel size or rating other than
that specified for your vehicle. Some combinations
of unapproved tires and wheels may change sus-
pension dimensions and performance characteris-
tics, resulting in changes to steering, handling, and
braking of your vehicle. This can cause unpredict-
able handling and stress to steering and suspen-
sion components. You could lose control and have
an accident resulting in serious injury or death. Use
only the tire and wheel sizes with load ratings
approved for your vehicle.
•Never use a tire with a smaller load index or
capacity, other than what was originally equipped
on your vehicle. Using a tire with a smaller load
index could result in tire overloading and failure.
You could lose control and have an accident.
•Failure to equip your vehicle with tires having
adequate speed capability can result in sudden tire
failure and loss of vehicle control.
CAUTION!
Replacing original tires with tires of a different size
may result in false speedometer and odometer read-
ings.
Alignment And Balance
Poor suspension alignment may result in:
•Fast tire wear.
•Uneven tire wear, such as feathering and one-sided
wear.
•Vehicle pull to right or left.
Tires may also cause the vehicle to pull to the left or right.
Alignment will not correct this condition. See your dealer
for proper diagnosis.
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Improper alignment will not cause vehicle vibration.
Vibration may be a result of tire and wheel out-of-
balance. Proper balancing will reduce vibration and
avoid tire cupping and spotty wear.
Low Tire Pressure (LTP) System
Low Tire Indicator
The Low Tire indicator in the Liquid Crystal Display
(LCD) of the instrument cluster will flash slowly and a
single chime will sound to warn if tire pressure falls
below 20 psi (138 kpa). The indicator will flash more
rapidly and a continuous tone will sound to warn if tire
pressure falls below 14 psi (97 kpa). Seek repair as soon as
possible.
If the indicator stays on and one chime will sound, a
system failure has occurred. See your dealer for service.
Although the tires are designed with a“run flat”feature
that allows the vehicle to be driven about 50 miles (80km) at 55 m.p.h. (88 kph), immediate service should be
obtained if the Low Tire indicator is activated.
WARNING!
Do not exceed 55 m.p.h. (88 k.p.h.) if the LOW Tire
indicator in the instrument cluster is illuminated.
Vehicle handling and braking may be reduced. You
could have an accident and be severely or fatally
injured.
NOTE:The“run flat”feature eliminates the need for a
spare tire and jack. This vehicle is not equipped with
either a spare tire or jack.
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CAUTION!
The Low Tire Pressure (LTP) system has been opti-
mized for the original equipment tires and wheels.
The LTP system pressures have been established for
the tire size equipped on your vehicle. Undesirable
operation or sensor damage may result when using
replacement equipment that is not of the same size,
type, and/or style. After-market wheels can cause
sensor damage. Do not use tire sealant or balance
beads if your vehicle is equipped with the LTP
system as damage to the sensors may result.
TIRE CHAINS
Due to limited clearance, tire chains are not recom-
mended.
CAUTION!
Damage to the vehicle may result if tire chains are
used.
SNOW TIRES
There are no snow tires that are compatible with the
wheels on this vehicle.
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Tire Storage
Tire storage is addressed in the Michelin Limited Tire
Warranty Booklet.
Specific recommendations on guidelines for long term
tire storage for this vehicle should be requested of the
Michelin Tire Corporation 1-800-433-6838.
Tire Rotation Recommendations
Do not rotate these tires as the wider rear tires will not fit
on the front of the vehicle.
Your vehicle has tires with directional tread, which will
also not allow switching tires from side to side.
GROUND CLEARANCE
The Viper is a low vehicle and ground clearance is
limited.
CAUTION!
Damage to the front and rear fascias and side sills
can occur if you disregard the low ground clearance
of your Viper. Pay close attention when parking to
avoid running into parking curbs. Exercise caution
when entering or exiting steep driveways or when
pulling off the road onto soft shoulders.
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FUEL REQUIREMENTS
Your vehicle is designed to meet all emis-
sion regulations and provide excellent fuel
economy when using high quality pre-
mium unleaded gasoline having an octane
rating of 91 or higher.
Spark Knock
Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage and immediate service is
required.
Poor quality gasoline can cause problems such as hard
starting, stalling and hesitations. If you experience these
symptoms, try another brand of“regular”gasoline be-
fore considering service for the vehicle.
Over 40 automobile manufacturers around the world
have issued and endorsed consistent gasoline specifica-
tions (the World Wide Fuel Charter, WWFC) to definefuel properties necessary to deliver enhanced emissions,
engine performance, and durability for your vehicle. The
manufacturer recommends the use of gasolines that meet
the WWFC specifications if they are available.
Reformulated Gasoline
Many areas of the country require the use of cleaner
burning fuel referred to as Reformulated Gasoline.
Reformulated gasolines contain oxygenates, and are spe-
cially blended to reduce vehicle emissions and improve
air quality.
The manufacturer strongly supports the use of reformu-
lated gasolines. Properly blended reformulated gasolines
will provide excellent performance and durability of
engine and fuel system components.
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Gasoline/Oxygenate Blends
Some fuel suppliers blend unleaded gasoline with mate-
rials called oxygenates such as 10% alcohol, MTBE, ETBE
or TAME. Oxygenates are required in some areas of the
country during the winter months to reduce carbon
monoxide emissions. Fuels blended with these oxygen-
ates may be used in your vehicle.
CAUTION!
DO NOT use gasolines containing METHANOL.
Gasoline containing methanol may damage critical
fuel system components.
MMT In Gasoline
MMT is a manganese containing metallic additive that is
blended into some gasoline to increase the octane. Gaso-
lines blended with MMT offer no performance advantage
beyond gasolines of the same octane number without
MMT. Gasolines blended with MMT reduce spark plug
life and reduce emission system performance in some
vehicles. The manufacturer recommends that gasolines
without MMT be used in your vehicle. The MMT content
of gasoline may not be indicated on the gasoline pump,
therefore, you should ask your gasoline retailer whether
or not his/her gasoline contains MMT.
It is even more important to look for gasolines without
MMT in Canada because MMT can be used at higher
levels than are allowed in the United States. MMT is
prohibited in Federal and California reformulated gaso-
lines.
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Materials Added to Fuel
All gasoline sold in the United States and Canada is
required to contain effective detergent additives. The use
of additional detergents or other additives is not needed
under normal conditions.
Fuel System Cautions
CAUTION!
Follow these guidelines to maintain your vehicle’s
performance:
•The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine performance,
or damage the emission control system.
•An out-of-tune engine, or certain fuel or ignition
malfunctions, can cause the catalytic converter to
overheat. If you notice a pungent burning odor orsome light smoke, your engine may be out-of-tune or
malfunctioning and may require immediate service.
Contact your dealer for service assistance.
•The use of fuel additives which are now being sold as
octane enhancers are not recommended. Most of these
products contain high concentrations of methanol.
Fuel system damage or vehicle performance problems
resulting from the use of such fuels or additives are not
the responsibility of the manufacturer.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
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