fuel Ram 2500 2015 Service Manual

Autostop, the Climate Controls system may automati-
cally adjust airflow to maintain cabin comfort. Customer
settings will be maintained upon return to an engine
running condition.
Possible Reasons The Engine Does Not Autostop
Prior to engine shut down, the system will check many
safety and comfort conditions to see if they are fulfilled.
In following situations the engine will not stop:
•Driver ’s seat belt is not buckled
• Driver ’s door is not closed
• Outside temperature is less than 1°F (–17°C) or greater
than 104°F (40°C)
• Battery temperature too warm or cold
• The vehicle is on a steep grade •
Cabin heating or cooling is in process and an accept-
able cabin temperature has not been achieved
• HVAC is set to full defrost mode at a high blower
speed
• Engine has not reached normal operating temperature
• Battery discharged
• The transmission is not in DRIVE
• Hood is open
• Vehicle is in 4LO transfer case mode
Other factors which can inhibit AutoStop include: fuel
level, accelerator pedal input, engine temp too high and
steering angle.
It may be possible for the vehicle to be driven several
times without the STOP/START system going into a
STOP/START READY state under more extreme condi-
tions of the items listed above.
448 STARTING AND OPERATING

CAUTION!
Towing the vehicle, coasting, or driving for any other
reason with the transmission in NEUTRAL can cause
severe transmission damage. Refer to “Recreational
Towing” in “Starting And Operating” and “Towing A
Disabled Vehicle” in “What To Do In Emergencies”
for further information.
DRIVE (D)
This range should be used for most city and highway
driving. It provides the smoothest upshifts and down-
shifts, and the best fuel economy. The transmission
automatically upshifts through all forward gears. The
DRIVE position provides optimum driving characteris-
tics under all normal operating conditions. When frequent transmission shifting occurs (such as
when operating the vehicle under heavy loading condi-
tions, in hilly terrain, traveling into strong head winds, or
while towing heavy trailers), select TOW/HAUL mode
or use the Electronic Range Select (ERS) shift control
(refer to
Electronic Range Select (ERS) Operation in this
section for further information) to select a lower gear
range. Under these conditions, using a lower gear range
will improve performance and extend transmission life
by reducing excessive shifting and heat buildup.
During extremely cold temperatures (-22°F [-30°C] or
below), transmission operation may be modified depend-
ing on engine and transmission temperature as well as
vehicle speed. Normal operation will resume once the
transmission temperature has risen to a suitable level.
460 STARTING AND OPERATING

CAUTION!
Towing the vehicle, coasting, or driving for any other
reason with the transmission in NEUTRAL can cause
severe transmission damage. Refer to “Recreational
Towing” in “Starting And Operating” and “Towing A
Disabled Vehicle” in “What To Do In Emergencies”
for further information.
DRIVE (D)
This range should be used for most city and highway
driving. It provides the smoothest upshifts and down-
shifts, and the best fuel economy. The transmission
automatically upshifts through underdrive first and sec-
ond gears, direct third gear and overdrive fourth and
fifth gears. The DRIVE position provides optimum driv-
ing characteristics under all normal operating conditions. To access all six available gears, you must use the
Electronic Range Select (ERS) shift control, described
below.
When frequent transmission shifting occurs (such as
when operating the vehicle under heavy loading condi-
tions, in hilly terrain, traveling into strong head winds, or
while towing heavy trailers), use the Electronic Range
Select (ERS) shift control (refer to “Electronic Range
Select (ERS) Operation” in this section for further infor-
mation) to select a lower gear range. Under these condi-
tions, using a lower gear range will improve performance
and extend transmission life by reducing excessive shift-
ing and heat buildup.
If the transmission temperature exceeds normal operat-
ing limits, the powertrain controller will modify the
transmission shift schedule and expand the range of
torque converter clutch engagement. This is done to
prevent transmission damage due to overheating.
5
STARTING AND OPERATING 469

The “TOW/HAUL Indicator Light” will illuminate in the
instrument cluster to indicate that TOW/HAUL mode has
been activated. Pushing the switch a second time restores
normal operation. Normal operation is always the default
at engine start-up. If TOW/HAUL mode is desired, the
switch must be pushed each time the engine is started.
WARNING!
Do not use the “TOW/HAUL” feature when driving
in icy or slippery conditions. The increased engine
braking can cause the rear wheels to slide, and the
vehicle to swing around with the possible loss of
vehicle control, which may cause an accident possi-
bly resulting in personal injury or death.
Torque Converter Clutch
A feature designed to improve fuel economy has been
included in the automatic transmission on your vehicle.
A clutch within the torque converter engages automati-
cally at calibrated speeds. This may result in a slightly
different feeling or response during normal operation in
the upper gears. When the vehicle speed drops or during
some accelerations, the clutch automatically disengages.
TOW/HAUL Switch
5
STARTING AND OPERATING 475

CAUTION!
Towing the vehicle, coasting, or driving for any other
reason with the transmission in NEUTRAL can cause
severe transmission damage. Refer to “Recreational
Towing” in “Starting And Operating” and “Towing A
Disabled Vehicle” in “What To Do In Emergencies”
for further information.
DRIVE (D)
This range should be used for most city and highway
driving. It provides the smoothest upshifts and down-
shifts, and the best fuel economy. The transmission
automatically upshifts through underdrive first, second,
and third gears, direct fourth gear and overdrive fifth and
sixth gears. The DRIVE position provides optimum driv-
ing characteristics under all normal operating conditions.
When frequent transmission shifting occurs (such as when
operating the vehicle under heavy loading conditions, in
hilly terrain, traveling into strong head winds, or while
towing heavy trailers), use the Electronic Range Select
(ERS) shift control (refer to “Electronic Range Select (ERS)
Operation” in this section for further information) to select
a lower gear range. Under these conditions, using a lower
gear range will improve performance and extend transmis-
sion life by reducing excessive shifting and heat buildup.
If the transmission temperature exceeds normal operat-
ing limits, the powertrain controller will modify the
transmission shift schedule and expand the range of
torque converter clutch engagement. This is done to
prevent transmission damage due to overheating.
If the transmission becomes extremely hot or is in danger
of overheating, the “Transmission Temperature Warning
Light” may illuminate and the transmission may operate
differently until the transmission cools down.
5
STARTING AND OPERATING 481

The “TOW/HAUL Indicator Light” will illuminate in the
instrument cluster to indicate that TOW/HAUL mode
has been activated. Pushing the switch a second time
restores normal operation. Normal operation is always
the default at engine start-up. If TOW/HAUL mode isdesired, the switch must be pushed each time the engine
is started.
WARNING!
Do not use the “TOW/HAUL” feature when driving
in icy or slippery conditions. The increased engine
braking can cause the rear wheels to slide, and the
vehicle to swing around with the possible loss of
vehicle control, which may cause an accident possi-
bly resulting in personal injury or death.
Torque Converter Clutch
A feature designed to improve fuel economy has been
included in the automatic transmission on your vehicle.
A clutch within the torque converter engages automati-
cally at calibrated speeds. This may result in a slightly
different feeling or response during normal operation in
TOW/HAUL Switch
486 STARTING AND OPERATING

•Four-wheel drive low range (4WD LOW)
• Neutral (NEUTRAL)
This electronically shifted transfer case is designed to be
driven in the two–wheel drive position (2WD) or four -
wheel drive position (4WD AUTO) for normal street and
highway conditions on dry hard surfaced roads). Driving
the vehicle in 2WD will have greater fuel economy
benefits as the front axle is not engaged in 2WD.
For variable driving conditions, the 4WD AUTO mode
can be used. In this mode, the front axle is engaged, but
the vehicle’s power is sent to the rear wheels. Four -
wheel drive will be automatically engaged when the
vehicle senses a loss of traction. Because the front axle is
engaged, this mode will result in lower fuel economy
than the 2WD mode. When additional traction is required, the transfer case
4WD LOCK and 4WD LOW positions can be used to
maximize torque to the front driveshaft, forcing the front
and rear wheels to rotate at the same speed. This is
accomplished by rotating the 4WD Control Switch to the
desired position. Refer to “Shifting Procedure” for spe-
cific shifting instructions. The 4WD LOCK and 4WD
LOW positions are designed for loose, slippery road
surfaces only. Driving in the 4WD LOCK and 4WD LOW
positions on dry hard surfaced roads may cause in-
creased tire wear and damage to the driveline compo-
nents.
NOTE:
The transfer case NEUTRAL position is selected
by pushing the button located on the lower left hand
corner of the 4WD Control Switch. The transfer case
NEUTRAL position is to be used for recreational towing
only. Refer to “Recreational Towing” in “Starting And
Operating” for further information.
5
STARTING AND OPERATING 499

This electronically shifted transfer case provides five
mode positions:
•Two-wheel drive high range (2WD)
• Four-wheel drive automatic range (4WD AUTO)
• Four-wheel drive lock range (4WD LOCK)
• Four-wheel drive low range (4WD LOW)
• Neutral (NEUTRAL)
This electronically shifted transfer case is designed to be
driven in the two–wheel drive position (2WD) or four-
wheel drive position (4WD AUTO) for normal street and
highway conditions on dry hard surfaced roads). Driving
the vehicle in 2WD will have greater fuel economy
benefits as the front axle is not engaged in 2WD.
For variable driving conditions, the 4WD AUTO mode
can be used. In this mode, the front axle is engaged, but
the vehicle’s power is sent to the rear wheels. Four-wheel drive will be automatically engaged when the vehicle
senses a loss of traction. Because the front axle is en-
gaged, this mode will result in lower fuel economy than
the 2WD mode.
When additional traction is required, the transfer case
4WD LOCK and 4WD LOW positions can be used to
maximize torque to the front driveshaft, forcing the front
and rear wheels to rotate at the same speed. This is
accomplished by rotating the 4WD Control Switch to the
desired position. Refer to “Shifting Procedure” for spe-
cific shifting instructions. The 4WD LOCK and 4WD
LOW positions are designed for loose, slippery road
surfaces only. Driving in the 4WD LOCK and 4WD LOW
positions on dry hard surfaced roads may cause in-
creased tire wear and damage to the driveline compo-
nents.
504 STARTING AND OPERATING

agency to determine the designated off-road vehicle
(ORV) trails or recreation areas. You should always tread
lightly and only use established roads, trails or ORV
recreational areas. The National Forest Service, Bureau of
Land Management or local Department of Natural Re-
sources are a wealth of information and usually have
maps with marked trails.
Skid Plates And Underbody Protection
Steel skid plates protect the major driveline components
of the truck including the fuel tank, transfer case and
steering damper. In addition, this vehicle is equipped
with boxed cross members and fore/aft rails. This addi-
tional protection allows the vehicle to be utilized in
severe off-road situations that would be considered im-
passable by a normal truck.
Ramp Travel Index (RTI)
The ramp travel index is the distance, in inches, that you
can drive your vehicle with one wheel on a 20-degree
ramp without lifting any other wheel off the ground. This
distance up the ramp divided by the wheelbase of the
vehicle and multiplied by 1,000 is the RTI. This vehicle
has an RTI of 510, which means you can articulate one
front wheel 26 inches (66 cm) in the air while the other
three wheels remain in contact with the ground.
Water Fording Characteristics
Water fording characteristic is the vehicle’s ability to cross
a body of still water, where the powertrain and drivetrain
are safe from water ingestion. This vehicle has high water
fording characteristics with the ability to cross a pool of
water, without stopping, 24 inches (60 cm) deep at a
maximum speed of 10 mph (16 km/h) and a pool of water
30 inches (76 cm) deep at a maximum speed of 5 mph
(8 km/h), both with an entrance ramp angle of 1.3 degrees.
5
STARTING AND OPERATING 527

After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road, it is
always a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
• Inspect the radiator for mud and debris and clean as
required.
• Check 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. •
Check for accumulations of plants or brush. These
things could be a fire hazard. They might hide damage
to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
• After extended operation in mud, sand, water, or
similar dirty conditions, have the radiator, fan, brake
rotors, wheels, 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 a collision. If you have been operating your
vehicle in dirty conditions, get your brakes checked
and cleaned as necessary.
544 STARTING AND OPERATING