2004 JEEP WRANGLER fuel

Traction Downhill
Shift the transmission into a low gear and transfer case to
4L (Low) range. Let the vehicle go slowly down the hill
with all four wheels turning against engine compression
drag. This will permit you to control the vehicle speed
and direction.
After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After driving off-road, it is
always a good idea to check for damage.
²Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
²Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
²Check for accumulations of plants or brush. These
things could be a fire hazard, or they might hide
damage to fuel lines, brake hoses, axle pinion seals,
and propeller shafts.
²After extended operation in mud, sand, water, or
similar dirty conditions, have brake drums, brake
linings, and axle yokes inspected and cleaned as soon
as possible.
WARNING!
Abrasive material in any part of the brakes may
cause excessive wear or unpredictable braking. You
might not have full braking power when you need it
to prevent an accident. If you have been operating
your vehicle in dirty conditions, get your brakes
checked and cleaned as necessary.
²If you experience unusual vibration after driving in
mud, slush or similar conditions, check the wheels for
packed material. Packed foreign material can cause a
wheel imbalance and freeing the wheels will correct
the situation.
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2. EconomyÐ
Improper inflation pressures can cause uneven wear
patterns to develop across the tire tread. These abnormal
wear patterns will reduce tread life resulting in a need for
earlier tire replacement. Under inflation also increases
tire rolling resistance and results in higher fuel consump-
tion.
3. Ride Comfort and Vehicle StabilityÐ
Proper tire inflation contributes to a comfortable ride.
Over inflation produces a jarring and uncomfortable ride.
Both under inflation and over inflation affect the stability
of the vehicle and can produce a feeling of sluggish
response or over-responsiveness in the steering.
Unequal tire pressures can cause erratic and unpredict-
able steering response.
Unequal tire pressure from side to side may cause the
vehicle to drift left or right.
Tire Inflation Pressures
The proper cold tire inflation pressure is located on the
lower driver's side instrument panel.
The tire pressure should be checked and adjusted at least
once every month. Check more often if subject to a wide
range of outdoor temperatures, as tire pressures vary
with temperature changes.
Inflation pressures specified on the label are always
ªCold Inflation Pressure.º Cold inflation pressure is
defined as the tire pressure after the vehicle has been idle
for at least 3 hours, or driven less than a mile after a 3
hour period. The cold inflation pressure must not exceed
the maximum values molded into the tire sidewall.
Tire pressures may increase from 13 to 40 kPa (2 to 6 psi)
[0.138 to 0.414 bar] during operation. DO NOT reduce
this normal pressure buildup.
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Follow the recommended tire rotation frequency for your
type of driving found in the ªMaintenance Schedulesº
Section of this manual. More frequent rotation is permis-
sible if desired. The reasons for any rapid or unusual
wear should be corrected prior to rotation being per-
formed.
The suggested rotation method is the ªforward-crossº
shown in the following diagram.FUEL REQUIREMENTS
Your engine is designed to meet all emis-
sions regulations and provide excellent
fuel economy and performance when us-
ing high quality unleaded gasoline having
an octane rating of 87. The use of premium
gasoline is not recommended. The use of
premium gasoline will provide no benefit over high
quality regular gasoline, and in some circumstances may
result in poorer performance.
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. Engine damage resulting from operation with a
heavy spark knock may not be covered by the new
vehicle warranty.
Poor quality gasoline can cause problems such as hard
starting, stalling and hesitations. If you experience these
symptoms, try another brand of gasoline before consid-
ering service for the vehicle.
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Over 40 auto manufacturer's world wide have issued and
endorsed consistent gasoline specifications (the World-
wide Fuel Charter, WWFC) to define fuel properties
necessary to deliver enhanced emissions, performance,
and durability for your vehicle. The manufacturer recom-
mends the use of gasoline that meets the WWFC speci-
fications if they are available.
Reformulated Gasoline
Many areas of the country require the use of cleaner
burning gasoline referred to as Reformulated Gasoline.
Reformulated gasoline contains oxygenates, and is spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
The manufacturer strongly supports the use of reformu-
lated gasoline. Properly blended reformulated gasoline
will provide excellent performance and durability for the
engine and fuel system components.
Gasoline/Oxygenate Blends
Some fuel suppliers blend unleaded gasoline with oxy-
genates such as 10% ethanol, MTBE, and ETBE. Oxygen-
ates are required in some areas of the country during thewinter months to reduce carbon monoxide emissions.
Fuels blended with these oxygenates may be used in
your vehicle.
CAUTION!
DO NOT use gasoline 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 octane. Gasoline
blended with MMT provides no performance advantage
beyond gasoline of the same octane number without
MMT. Gasoline blended with MMT reduces spark plug
life and reduces emission system performance in some
vehicles. The manufacturer recommends that gasoline
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.
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It is even more important to look for gasoline without
MMT in Canada because MMT can be used at levels
higher than allowed in the United States. MMT is pro-
hibited in Federal and California reformulated gasoline.
Sulfur In Gasoline
If you live in the northeast United States, your vehicle
may have been designed to meet California low emission
standards with clean burning, low sulfur, California
gasoline. Gasoline sold outside of California is permitted
to have higher sulfur levels which may affect the perfor-
mance of the vehicle's catalytic converter. This may cause
the ªMalfunction Indicator Lightº to illuminate.
Illumination of this light while operating on high sulfur
gasoline does not necessarily mean your emission control
system is malfunctioning. The manufacturer recom-
mends that you try a different brand of unleaded gaso-
line having lower sulfur to determine if the problem is
fuel related prior to returning your vehicle to an autho-
rized dealer for service.
CAUTION!
If the ªMalfunction Indicator Lightº is flashing,
immediate service is required. See ªOnboard Diag-
nostic Systemº in Section 7 of this manual.
Materials Added To Fuel
All gasoline sold in the United States is required to
contain effective detergent additives. Use of additional
detergents or other additives is not needed under normal
conditions.
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FUEL FILLER CAP (GAS CAP)
The fuel cap is located on the left side of the vehicle. If the
fuel cap is lost or damaged, be sure the replacement cap
is for use with this vehicle.CAUTION!
Damage to the fuel system or emission control
system could result from using an improper fuel cap
(gas cap). A poorly fitting cap could let impurities
into the fuel system. Also, a poorly fitting after-
market cap can cause the MIL (Malfunction Indica-
tor Light) to illuminate, due to fuel vapors escaping
from the system.
²Turn the engine off.
²Rotate the fuel cap to the left to remove.
²To replace the cap, insert it into the filler neck and
tighten the cap about 1/4 turn until you hear one click.
This is an indication that the cap is properly tightened.
²Make sure that the fuel cap tether strap is not caught
under the fuel cap.
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CAUTION!
To avoid fuel spillage and overfilling, do not ªtop
offº the fuel tank after filling.
NOTE:When the fuel nozzle ªclicksº or shuts off, the
fuel tank is full.
WARNING!
²Remove the fuel cap (gas cap) slowly to prevent
fuel spray from the filler neck which may cause
injury.
²The volatility of some gasoline may cause a
buildup of pressure in the fuel tank that may
increase while you drive. This pressure can result
in a spray of gasoline and/or vapors when the cap
is removed from a hot vehicle. Removing the cap
slowly allows the pressure to vent and prevents
fuel spray.
²Never have any smoking materials lit in or near
the vehicle when the fuel cap is removed or the
tank filled.
²Never add fuel to the vehicle when the engine is
running.
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WARNING!
A fire may result if gasoline is pumped into a
portable container that is inside of a vehicle. You
could be burned. Always place gas containers on the
ground while filling.
Locking Fuel Filler Cap (Gas Cap) Ð If Equipped
²
Turn the engine off.
²Insert the ignition key into the fuel cap, and turn the
key to the right to unlock the fuel cap. Rotate the fuel
cap to the left to remove.
²To replace the cap, insert it into the filler neck and
tighten the cap about 1/4 turn until you hear one click.
This is an indication that the cap is properly tightened.
²Make sure that the fuel cap tether strap is not caught
under the fuel cap.
²Be sure to remove the key.
CAUTION!
To avoid fuel spillage and overfilling, do not ªtop
offº the fuel tank after filling.
NOTE:When the fuel nozzle ªclicksº or shuts off, the
fuel tank is full.
TRAILER TOWING
In this section you will find information on limits to the
type of towing you can reasonably do with your vehicle.
Before towing a trailer, carefully review 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.
Perform maintenance services as prescribed in the
ªMaintenance Schedulesº section. When your vehicle is
used for trailer towing, never exceed the gross axle
weight rating (GAWR) by the addition of:
²The tongue weight of the trailer.
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