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as specified by the (R+M)/2 method. The use of 89 octane
“Plus” gasoline is recommended for optimum perfor-
mance and fuel economy.
While operating on gasoline with an octane number of
87, hearing a light knocking sound from the engine is not
a cause for concern. However, if the engine is heard
making a heavy knocking sound, see your dealer imme-
diately. Use of gasoline with an octane number lower
than 87 can cause engine failure and may void or not be
covered by the New Vehicle Limited 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.
Reformulated Gasoline
Many areas of the country require the use of cleaner
burning gasoline referred to as “Reformulated Gasoline”.Reformulated gasoline contains oxygenates and are spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
The use of reformulated gasoline is recommended. Prop-
erly blended reformulated gasoline will provide im-
proved performance and durability of engine and fuel
system components.
Gasoline/Oxygenate Blends
Some fuel suppliers blend unleaded gasoline with oxy-
genates such as ethanol.
CAUTION!
DO NOT use gasoline containing methanol or gaso-
line containing more than 15% ethanol (E-15). Use of
these blends may result in starting and drivability
problems, damage critical fuel system components,
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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
the gasoline contains MMT. MMT is prohibited in Federal
and California reformulated gasoline.
Materials Added To Fuel
Besides using unleaded gasoline with the proper octane
rating, gasolines that contain detergents, corrosion and
stability additives are recommended. Using gasolines
that have these additives will help improve fuel
economy, reduce emissions, and maintain vehicle perfor-
mance. Designated TOP TIER Detergent Gasoline con-
tains a higher level of detergents to further aide in
minimizing engine and fuel system deposits. When avail-
able the usage of Top Tier Detergent gasoline is recom-
mended. Visit www.toptiergas.com for a list of TOP TIER
Detergent Gasoline Retailers.Indiscriminate use of fuel system cleaning agents should
be avoided. Many of these materials intended for gum
and varnish removal may contain active solvents or
similar ingredients. These can harm fuel system gasket
and diaphragm materials.
Fuel System Cautions
CAUTION!
Follow these guidelines to maintain your vehicle’s
performance:
•The use of leaded gasoline is prohibited by Federal
law. Using leaded gasoline can impair engine per-
formance and damage the emissions control sys-
tem.
•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 or
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CAUTION!(Continued)
some light smoke, your engine may be out of tune
or malfunctioning and may require immediate ser-
vice. Contact your authorized dealer for service
assistance.
•The use of fuel additives, which are now being
sold as octane enhancers, is not recommended.
Most of these products contain high concentrations
of methanol. Fuel system damage or vehicle perfor-
mance problems resulting from the use of such
fuels or additives is not the responsibility of the
manufacturer and may void or not be covered
under the New Vehicle Limited Warranty.
NOTE:Intentional tampering with the emissions control
system can result in civil penalties being assessed against
you.
Carbon Monoxide Warnings
WARNING!
Carbon monoxide (CO) in exhaust gases is deadly.
Follow the precautions below to prevent carbon
monoxide poisoning:
•Do not inhale exhaust gases. They contain carbon
monoxide, a colorless and odorless gas, which can
kill. Never run the engine in a closed area, such as
a garage, and never sit in a parked vehicle with the
engine running for an extended period. If the
vehicle is stopped in an open area with the engine
running for more than a short period, adjust the
ventilation system to force fresh, outside air into
the vehicle.
•Guard against carbon monoxide with proper main-
tenance. Have the exhaust system inspected every
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5
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WARNING!(Continued)
time the vehicle is raised. Have any abnormal
conditions repaired promptly. Until repaired, drive
with all side windows fully open.
FLEXIBLE FUEL (3.6L ENGINE ONLY) — IF
EQUIPPED
E-85 General Information
The information in this section is unique for Flexible Fuel
vehicles only. These vehicles can be identified by a
unique fuel filler door label that statesEthanol (E-85) or
Unleaded Gasoline Onlyand a yellow fuel cap. Please
refer to the other sections of this manual for information
on features that are common between Flexible Fuel and
non-Flexible Fuel powered vehicles.
CAUTION!
Only vehicles with the E-85 fuel filler door label or a
yellow gas cap can operate on E-85.
Ethanol Fuel (E-85)
E-85 is a mixture of approximately 85% ethanol and 15%
unleaded gasoline.
WARNING!
Ethanol vapors are extremely flammable and could
cause serious personal injury. Never have any smok-
ing materials lit or products that can cause spark in or
near the vehicle when removing the fuel filler tube
cap (gas cap) or filling the tank. Do not use E-85 as a
cleaning agent and never use it near an open flame.
680 STARTING AND OPERATING
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Recommended Distribution Hitch Adjustment
Towing With 1500 Air Suspension
1. Set air suspension to normal ride height. No action is
required if already in normal ride height.
NOTE:The vehicle must remain in the engine running
position while attaching a trailer for proper leveling of
the air suspension system.
2. Position the truck to be ready to connect to the trailer
(do not connect the trailer).
3. Under radio suspension settings, turn on jack mode.
Jack mode will be canceled and procedure must be
restarted if the vehicle is driven at speeds above 5mph
(8kph).
4. Measure the height of the top of the front wheel
opening on the fender to ground, this is height H1.
Improper Adjustment Of Weight-Distributing Hitch
(Incorrect)
5
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NOTE:For all towing conditions, we recommend towing
with tow haul mode engaged.
All Other 1500(Non-Air Suspension)/2500/3500 Trucks
1. Position the truck to be ready to connect to the trailer
(do not connect the trailer).
NOTE:For Ram 2500/3500 trucks equipped with rear air
suspension, normal ride height or alternate ride height
can be used. The vehicle must remain in the engine
running position while attaching a trailer for proper
leveling of the air suspension system. It may not be
possible to enter alternate ride height while lightly
loaded.
2. Measure the height of the top of the front wheel
opening on the fender to ground, this is height H1.
3. Attach the trailer to the vehicle without the weight
distribution bars connected.4. Measure the height of the top of the front wheel
opening on the fender to ground, this is height H2.
5. Install and adjust the tension in the weight distribut-
ing bars so that the height of the front fender is
approximately (H2-H1)/2+H1 (about 1/2 the differ-
ence between H2 and H1 above normal ride height
[H1]).
Measurement ExampleExample 2500/3500
Height (mm)
H1 1030
H2 1058
H2-H1 28
(H2-H1)/2 14
(H2-H1)/2 + H1 1044
NOTE:For all towing conditions, we recommend towing
with tow haul mode engaged.
5
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CAUTION!
Connecting a trailer that is not compatible with the
ITBM system may result in reduced or complete loss
of trailer braking. There may be a increase in stop-
ping distance or trailer instability which could result
in damage to your vehicle, trailer, or other property.
WARNING!
Connecting a trailer that is not compatible with the
ITBM system may result in reduced or complete loss
of trailer braking. There may be a increase in stop-
ping distance or trailer instability which could result
in personal injury.NOTE:
•An aftermarket controller may be available for use
with trailers with air or electric-over-hydraulic trailer
brake systems. To determine the type of brakes on
your trailer and the availability of controllers, check
with your trailer manufacturer or dealer.
•Removal of the ITBM will cause errors and it may
cause damage to the electrical system and electronic
modules of the vehicle. See your authorized dealer if
an aftermarket module is to be installed.
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Air Conditioning
Turn off temporarily.
Air Suspension System
To aid in attaching/detaching the trailer from the vehicle,
the air suspension system can be used. Refer to “Air
Suspension System” in “Starting And Operating” for
further information.
NOTE:The vehicle must remain in the engine running
position while attaching a trailer for proper leveling of
the air suspension system.
SNOWPLOW
1500 Models Only
NOTE:Do not use this model vehicle for snowplow
applications.
WARNING!
Snowplows and other aftermarket equipment should
not be added to the front end of your vehicle. The
airbag crash sensors may be affected by the change in
the front end structure. The airbags could deploy
unexpectedly or could fail to deploy during a colli-
sion resulting in serious injury or death.
CAUTION!
Using this vehicle for snowplow applications can
cause damage to the vehicle.
WARNING!
Attaching a snowplow to this vehicle could adversely
affect performance of the airbag system in a collision.
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710 STARTING AND OPERATING