maint Ram 2500 2017 Service Manual

Disabling HDC
HDC will be deactivated and disabled if any of the
following conditions occur:
•The driver pushes the HDC switch.
• The driveline is shifted out of 4WD Low Range.
• The parking brake is applied.
• Driver door opens.
• The vehicle is driven greater than 20 mph (32 km/h) for
greater than 70 seconds.
• The vehicle is driven greater than 40 mph (64 km/h)
(HDC exits immediately).
• HDC detects excessive brake temperature.
Feedback To The Driver
The instrument cluster has an HDC icon and the HDC
switch has an LED which offer feedback to the driver about
the state HDC is in.
• The cluster icon and switch lamp will illuminate and
remain on solid when HDC is enabled or activated. This
is the normal operating condition for HDC. •
The cluster icon and switch lamp will flash for several
seconds then extinguish when the driver pushes the
HDC switch but enable conditions are not met.
• The cluster icon and switch lamp will flash for several
seconds then extinguish when HDC disables due to
excess speed.
• The cluster icon and switch lamp will flash when HDC
deactivates due to overheated brakes. The flashing will
stop and HDC will activate again once the brakes have
cooled sufficiently.
WARNING!
HDC is only intended to assist the driver in controlling
vehicle speed when descending hills. The driver must
remain attentive to the driving conditions and is re-
sponsible for maintaining a safe vehicle speed.
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Example: If garage temperature = 68°F (20°C) and the
outside temperature = 32°F (0°C) then the cold tire inflation
pressure should be increased by 3 psi (21 kPa), which
equals 1 psi (7 kPa) for every 12°F (7°C) for this outside
temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build up or your tire pressure will be too low.
Tire Pressures For High Speed Operation
The manufacturer advocates driving at safe speeds and
within posted speed limits. Where speed limits or condi-
tions are such that the vehicle can be driven at high speeds,
maintaining correct tire inflation pressure is very impor-
tant. Increased tire pressure and reduced vehicle loading
may be required for high-speed vehicle operation. Refer to
your authorized tire dealer or original equipment vehicle
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle under maximum
load is dangerous. The added strain on your tires could
cause them to fail. You could have a serious collision.
Do not drive a vehicle loaded to the maximum capacity
at continuous speeds above 75 mph (120 km/h).
Radial Ply Tires
WARNING!
Combining radial ply tires with other types of tires on
your vehicle will cause your vehicle to handle poorly.
The instability could cause a collision. Always use
radial ply tires in sets of four. Never combine them
with other types of tires.
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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 re-
placed.These indicators are molded into the bottom of the tread
grooves. They will appear as bands when the tread depth
becomes a 1/16 of an inch (1.6 mm). When the tread is
worn to the tread wear indicators, the tire should be
replaced. Refer to “Replacement Tires” in this section for
further information.
Life Of Tire
The service life of a tire is dependent upon varying factors
including, but not limited to:
•
Driving style.
• Tire pressure – Improper cold tire inflation pressures can
cause uneven wear patterns to develop across the tire
tread. These abnormal wear patterns will reduce tread
life, resulting in the need for earlier tire replacement.
• Distance driven.
• Performance tires, tires with a speed rating of V or
higher, and Summer tires typically have a reduced tread
life. Rotation of these tires per the vehicle maintenance
schedule is highly recommended.
Tire Tread
1—WornTire
2—NewTire 526 STARTING AND OPERATING

CAUTION!
To avoid damage to your vehicle or tires, observe the
following precautions:
•Because of restricted traction device clearance be-
tween tires and other suspension components, it is
important that only traction devices in good condi-
tion are used. Broken devices can cause serious
damage. Stop the vehicle immediately if noise occurs
that could indicate device breakage. Remove the
damaged parts of the device before further use.
• Install device as tightly as possible and then re-
tighten after driving about ½ mile (0.8 km).
• Do not exceed 30 mph (48 km/h).
• Drive cautiously and avoid severe turns and large
bumps, especially with a loaded vehicle.
• Do not drive for a prolonged period on dry pave-
ment.
• Observe the traction device manufacturer ’s instruc-
tions on the method of installation, operating speed,
and conditions for use. Always use the suggested
operating speed of the device manufacturer ’s if it is
less than 30 mph (48 km/h).
• Do not use traction devices on a compact spare tire.
TIRE ROTATION RECOMMENDATIONS
Tires on the front and rear axles of vehicles operate at
different loads and perform different steering, driving, and
braking functions. For these reasons, they wear at unequal
rates.
These effects can be reduced by timely rotation of tires. The
benefits of rotation are especially worthwhile with aggres-
sive tread designs such as those on all season type tires.
Rotation will increase tread life, help to maintain mud,
snow and wet traction levels and contribute to a smooth,
quiet ride.
Refer to the “Maintenance Schedule” for the proper main-
tenance intervals. More frequent rotation is permissible if
desired. The reasons for any rapid or unusual wear should
be corrected prior to rotation being performed.
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CAUTION!
•3500 Dual Rear Tires may only have one approved
direction of rotation. This is to accommodate the
asymmetrical design (tread pattern) of the On/Off-
Road tire and the use of Outline White Letter (OWL)
tires.
•
When replacing a flat, the spare tire may have to be
remounted on the rim, or installed at a different
location, to maintain the correct placement of the tire
on the wheel relative to the tire/wheel position on the
truck. For example, if the spare is used to replace an
outer rear tire it will have to be remounted on the rim
so that the wheel is dished inward. That way the tread
design of asymmetrical tires and the white writing of
the OWL tires will maintain proper position.
DEPARTMENT OF TRANSPORTATION UNIFORM
TIRE QUALITY GRADES
The following tire grading categories were established by
the National Highway Traffic Safety Administration. The
specific grade rating assigned by the tire’s manufacturer in
each category is shown on the sidewall of the tires on your
vehicle.
All passenger vehicle tires must conform to Federal safety
requirements in addition to these grades.
Treadwear
The Treadwear grade is a comparative rating, based on the
wear rate of the tire when tested under controlled condi-
tions on a specified government test course. For example, a
tire graded 150 would wear one and one-half times 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.
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CAUTION!
•The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures and
warning have been established for the tire size
equipped on your vehicle. Undesirable system op-
eration or sensor damage may result when using
replacement equipment that is not of the same size,
type, and/or style. Aftermarket wheels can cause
sensor damage.
• Using aftermarket tire sealants may cause the Tire
Pressure Monitoring System (TPMS) sensor to be-
come inoperable. After using an aftermarket tire
sealant it is recommended that you take your vehicle
to an authorized dealership to have your sensor
function checked.
• After inspecting or adjusting the tire pressure always
reinstall the valve stem cap. This will prevent mois-
ture and dirt from entering the valve stem, which
could damage the TPMS sensor.
NOTE:
• The TPMS is not intended to replace normal tire care and
maintenance or to provide warning of a tire failure or
condition. •
The TPMS should not be used as a tire pressure gauge
while adjusting your tire pressure.
• Driving on a significantly under-inflated tire causes the
tire to overheat and can lead to tire failure. Under-
inflation also reduces fuel efficiency and tire tread life,
and may affect the vehicle’s handling and stopping
ability.
• The TPMS is not a substitute for proper tire mainte-
nance, and it is the driver ’s responsibility to maintain
correct tire pressure using an accurate tire pressure
gauge, even if under-inflation has not reached the level
to trigger illumination of the “Tire Pressure Monitoring
Telltale Light.”
• Seasonal temperature changes will affect tire pressure,
and the TPMS will monitor the actual tire pressure in the
tire.
Premium System
The Tire Pressure Monitor System (TPMS) uses wireless
technology with wheel rim mounted electronic sensors to
monitor tire pressure levels. Sensors mounted to each
wheel as part of the valve stem transmit tire pressure
readings to the receiver module.
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NOTE:It is particularly important for you to check the tire
pressure in all of the tires on your vehicle monthly and to
maintain the proper pressure.
The TPMS consists of the following components:
• Receiver module
• Four TPM sensors
• Various TPMS messages, which display in the instru-
ment cluster
• TPM Telltale Light
Tire Pressure Monitoring Low Pressure Warnings
The “Tire Pressure Monitoring Telltale Light” will
illuminate in the instrument cluster and a chime
will sound when tire pressure is low in one or more of the
four active road tires. In addition, the instrument cluster
will display a “LOW TIRE” message and a graphic show-
ing the pressure values of each tire with the low tire
pressure values in a different color. An Inflate to XX
message will also be displayed. Should this occur, you should stop as soon as possible and
inflate the tires with a low pressure condition (those in a
different color in the instrument cluster graphic) to the
vehicle’s recommended cold placard pressure inflation
value as shown in the
Inflate to XXmessage. Once the
system receives the updated tire pressures, the system will
automatically update, the graphic display in the instru-
ment cluster will return to it’s original color, and the “Tire
Pressure Monitoring Telltale Light” will turn off. The
vehicle may need to be driven for up to 20 minutes above
15 mph (24 km/h) in order for the TPMS to receive this
information.
“LOW TIRE PRESSURE” Message
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switch cycle, the TPM Telltale Light and a “LOW TIRE”
message will remain ON and a chime will sound. In
addition, the graphic in the instrument cluster will still
display a pressure value in a different color.
• For each subsequent ignition switch cycle, a chime will
sound, the TPM Telltale Light will flash on and off for 75
seconds and then remain on solid, and the instrument
cluster will display a SERVICE TPM SYSTEM message
for a minimum of five seconds and then display dashes
(- -) in place of the pressure value.
• Once you repair or replace the original road tire and
reinstall it on the vehicle in place of the non matching
full size spare or compact spare, the TPMS will update
automatically. In addition, the TPM Telltale Light will
turn OFF and the graphic in the instrument cluster will
display a new pressure value instead of dashes (- -). The
vehicle may need to be driven for up to 20 minutes
above 15 mph (24 km/h) in order for the TPMS to
receive this information.
Tire Pressure Information System (TPIS) 3500
Series Trucks
Your vehicle may be equipped with a Tire Pressure Infor-
mation System (TPIS). The Tire Pressure Information System (TPIS) uses wireless
technology with wheel rim mounted electronic sensors to
transmit tire pressure levels. Sensors mounted to each
wheel as part of the valve stem transmit tire pressure
readings to the receiver module.
NOTE:
It is particularly important for you to check the tire
pressure in all of the tires on your vehicle monthly and to
maintain the proper pressure.
The TPIS consists of the following components:
• Receiver module
• Four TPM sensors (Single Rear Wheel (SRW) applica-
tions)
• Six TPM sensors (Dual Rear Wheel (DRW) applications)
• Pressure display in the instrument cluster
The TPIS system will display all four (Single Rear Wheel
(SRW) applications) or six (Dual Rear Wheel (DRW) appli-
cations) tire pressure values in the instrument cluster
display.
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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 performance.Designated TOP TIER Detergent Gaso-
line contains 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 recommended. 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 dia-
phragm 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 perfor-
mance and damage the emissions 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 or
some light smoke, your engine may be out of tune or
malfunctioning and may require immediate service.
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 metha-
nol. Fuel system damage or vehicle performance
problems resulting from the use of such fuels or
additives is not the responsibility of the manufac-
turer and may void or not be covered under the New
Vehicle Limited Warranty.
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additional requirements, developed during extensive fleet
testing, to provide additional protection to FCA US LLC
engines.
Starting
The characteristics of E-85 fuel make it unsuitable for use
when ambient temperatures fall below 0°F (-18°C). In the
range of 0°F (-18°C) to 32°F (0°C), an increase in the time it
takes for your engine to start may be experienced, and a
deterioration in driveability (sags and/or hesitations) until
the engine is fully warmed up. These issues may be
improved with the use of seasonally adjusted E-85 fuel.
NOTE:Use of the engine block heater (if equipped) may
improve engine start time when using E-85 fuel when the
ambient temperature is less than 32°F (0°C).
Cruising Range
Because E-85 fuel contains less energy per gallon/liter than
gasoline, an increase in fuel consumption will be experi-
enced. The miles per gallon (mpg)/kilometers per liter and
the driving range will decrease by approximately 30%,
compared to gasoline operation.
Replacement Parts
All fuel and engine components in your Flexible Fuel
Vehicle (FFV) are designed to be compatible with ethanol.
Ethanol compatible service components are required.
CAUTION!
Replacing fuel system components with non-ethanol
compatible components can damage your vehicle.
Maintenance
CAUTION!
Do not use ethanol mixtures greater than 85% in your
vehicle. It will make it more difficult for your engine to
start under cold conditions, may affect drivability, and
could cause engine damage.
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