2021 RAM CHASSIS CAB cooling

STARTING AND OPERATING149
REVERSE (R)
This range is for moving the vehicle backward.
Shift into REVERSE only after the vehicle has
come to a complete stop.
NEUTRAL (N)
Use this range when the vehicle is standing
for prolonged periods with the engine running.
The engine may be started in this range. Apply
the parking brake and shift the transmission
into PARK if you must exit the vehicle. DRIVE (D)
This range should be used for most city and
highway driving. It provides the smoothest
upshifts and downshifts, and the best fuel
economy. The transmission automatically
upshifts through all forward gears.
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
a heavy trailer), select TOW/HAUL mode or use
the Electronic Range Select (ERS) shift control
to select a lower gear range
Úpage 150. Under
these conditions, using a lower gear range will
improve performance and extend transmission
life by reducing excessive shifting and heat
buildup.

If the transmission temperature exceeds normal
operating 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.
NOTE:
Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer
up a steep grade, or in stop-and-go traffic)
during hot weather. In these conditions, torque
converter slip can impose a significant addi
-
tional heat load on the cooling system. Down -
shifting the transmission to the lowest possible
gear (when climbing a grade), or shifting to
NEUTRAL (when stopped in heavy traffic) can
help to reduce this excess heat generation.
During cold temperatures, transmission
operation may be modified depending on
engine and transmission temperature as well
as vehicle speed. This feature improves
warm-up time of the engine and transmission to
achieve maximum efficiency. Engagement of
the torque converter clutch is inhibited until the
transmission fluid is warm Ú page 151.
WARNING!

Do not coast in NEUTRAL and never turn off the
ignition to coast down a hill. These are unsafe
practices that limit your response to changing
traffic or road conditions. You might lose
control of the vehicle and have a collision.

CAUTION!

Towing the vehicle, coasting, or driving for any
other reason with the transmission in NEUTRAL
can cause severe transmission damage.

For Towing A Disabled Vehicle Ú page 350.
For Recreational Towing Ú page 215.
4

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SAFETY333
EXHAUST GAS The best protection against carbon monoxide
entry into the vehicle body is a properly
maintained engine exhaust system.

Whenever a change is noticed in the sound of
the exhaust system, when exhaust fumes can
be detected inside the vehicle, or when the
underside or rear of the vehicle is damaged, have
an authorized dealer inspect the complete
exhaust system and adjacent body areas for
broken, damaged, deteriorated, or mispositioned
parts. Open seams or loose connections could
permit exhaust fumes to seep into the passenger
compartment. In addition, inspect the exhaust
system each time the vehicle is raised for
lubrication or oil change. Replace as required.
CARBON MONOXIDE WARNINGS
WARNING!

Exhaust gases can injure or kill. They contain
carbon monoxide (CO), which is colorless
and odorless. Breathing it can make you
unconscious and can eventually poison you.
To avoid breathing (CO), follow these safety tips:

Do not run the engine in a closed garage or
in confined areas any longer than needed
to move your vehicle in or out of the area.
If you are required to drive with the trunk/
liftgate/rear doors open, make sure that all
windows are closed and the climate control
BLOWER switch is set at high speed.
DO NOT use the recirculation mode.
If it is necessary to sit in a parked vehicle
with the engine running, adjust your
heating or cooling controls to force outside
air into the vehicle. Set the blower at high
speed.
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 maintenance. Have the exhaust
system inspected every time the vehicle is
raised. Have any abnormal conditions
repaired promptly. Until repaired, drive with
all side windows fully open.
6

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IN CASE OF EMERGENCY345
3. If using another vehicle to jump start the
battery, park the vehicle within the jumper
cables reach, apply the parking brake, and
make sure the ignition is OFF.JUMP STARTING PROCEDURE
NOTE:
Make sure at all times that unused ends of
jumper cables are not contacting each other or
either vehicle while making connections.
Connecting The Jumper Cables

1. Connect the positive
(+) end of the jumper
cable to the positive (+)
post of the
discharged vehicle.

NOTE:
Do not jump off fuses. Only jump directly off
positive post. 2. Connect the opposite end of the positive
(+)
jumper cable to the positive (+) post of the
booster battery.
3. Connect the negative (-) end of the jumper
cable to the negative (-) post of the booster
battery.
4. Connect the opposite end of the negative (-)
jumper cable to a good engine ground.
A “ground” is an exposed metallic/
unpainted part of the engine, frame or
chassis, such as an accessory bracket or
large bolt. The ground must be away from
the battery and fuel injection system.
5. Start the engine in the vehicle that has the booster battery, let the engine idle a few
minutes, and then start the engine in the
vehicle with the discharged battery.
WARNING!
Take care to avoid the radiator cooling fan
whenever the hood is raised. It can start
anytime the ignition switch is ON. You can
be injured by moving fan blades.
Remove any metal jewelry such as rings,
watch bands and bracelets that could
make an inadvertent electrical contact.
You could be seriously injured.
Batteries contain sulfuric acid that can
burn your skin or eyes and generate
hydrogen gas which is flammable and
explosive. Keep open flames or sparks
away from the battery.
WARNING!
Do not allow vehicles to touch each other as
this could establish a ground connection and
personal injury could result.
WARNING!
Failure to follow this jump starting procedure
could result in personal injury or property
damage due to battery explosion.
CAUTION!
Failure to follow these procedures could
result in damage to the charging system of
the booster vehicle or the discharged vehicle.
WARNING!
Do not connect the jumper cable to the
negative (-) post of the discharged battery.
The resulting electrical spark could cause the
battery to explode and could result in
personal injury.7

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346IN CASE OF EMERGENCY
6. Once the engine is started, follow the
disconnecting procedure below.
Disconnecting The Jumper Cables

1. Disconnect the negative
(-)
end of the
jumper cable from the engine ground of
the vehicle with the discharged battery.

2. Disconnect the opposite end of the negative (-) jumper cable from the
negative (-) post of the booster battery.
3. Disconnect the positive (+) end of the
jumper cable from the positive (+) post of
the booster battery.
4. Disconnect the opposite end of the positive (+) jumper cable from the
positive (+) post of the vehicle with the
discharged battery.
If frequent jump starting is required to start your
vehicle you should have the battery and charging
system inspected at an authorized dealer.

IF YOUR ENGINE OVERHEATS
In any of the following situations, you can
reduce the potential for overheating by taking
the appropriate action.
On the highways — slow down.
In city traffic — while stopped, place the trans
-
mission in NEUTRAL, but do not increase the
engine idle speed while preventing vehicle
motion with the brakes. NOTE:
There are steps that you can take to slow down
an impending overheat condition:
If your Air Conditioner (A/C) is on, turn it off.
The A/C system adds heat to the engine
cooling system and turning the A/C off can
help remove this heat.
You can also turn the temperature control to
maximum heat, the mode control to floor and
the blower control to high. This allows the
heater core to act as a supplement to the
radiator and aids in removing heat from the
engine cooling system.
CAUTION!
Do not connect jumper cable to any of the
fuses on the positive battery terminal. The
resulting electrical current will blow the fuse.
CAUTION!

Accessories plugged into the vehicle power
outlets draw power from the vehicle’s battery,
even when not in use (i.e., cellular devices,
etc.). Eventually, if plugged in long enough
without engine operation, the vehicle’s battery
will discharge sufficiently to degrade battery
life and/or prevent the engine from starting.

WARNING!
You or others can be badly burned by hot
engine coolant (antifreeze) or steam from
your radiator. If you see or hear steam coming
from under the hood, do not open the hood
until the radiator has had time to cool. Never
try to open a cooling system pressure cap
when the radiator or coolant bottle is hot.

21_DPF_OM_EN_USC_t.book Page 346

IN CASE OF EMERGENCY347
GEAR SELECTOR OVERRIDE — 6–SPEED
TRANSMISSION
In order to move the vehicle in cases where the
transmission will not shift out of PARK (P) (such
as a depleted battery), a Manual Park Release
is available.

1. Turn the engine OFF.

2. Firmly apply the parking brake.
3. Tilt the steering wheel to the full up position.
4. Press and maintain firm pressure on the
brake pedal. 5. Insert a screwdriver or similar tool into the
access port (ringed circle) on the bottom of
the steering column, and push and hold the
override release lever up.

Gear Selector Override Access Port Location Gear Selector Override Access Port Engaging The Access Port

6. Move the gear selector to the NEUTRAL position.
7. The vehicle may then be started in NEUTRAL.
CAUTION!
Driving with a hot cooling system could
damage your vehicle. If the temperature
gauge reads HOT (H), pull over and stop the
vehicle. Idle the vehicle with the air
conditioner turned off until the pointer drops
back into the normal range. If the pointer
remains on HOT (H), and you hear continuous
chimes, turn the engine off immediately and
call for service.
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354SERVICING AND MAINTENANCE
MAINTENANCE PLAN
Refer to the maintenance plan on the following
pages for required maintenance. More frequent
maintenance may be needed in severe
conditions, such as dusty areas and very short
trip driving. In some extreme conditions,
additional maintenance not specified in the
maintenance schedule may be required.
NOTE:
Using white lithium grease, lubricate the door
hinge pivot joints twice a year to prevent prema-
ture wear.
At Every Oil Change Interval As Indicated By Oil Change Indicator System:
Change oil and filter.
Rotate the tires. Rotate at the first sign of
irregular wear, even if it occurs before the
oil indicator system turns on.
Inspect engine cooling system protection
and hoses.
Inspect exhaust system.
Inspect engine air cleaner filter if using in
dusty or off-road conditions. Replace the
engine air cleaner filter, if necessary.
Inspect battery and clean and tighten termi -
nals as required.
Inspect the CV/Universal joints.
Inspect automatic transmission fluid if
equipped with dipstick.
Inspect brake pads, shoes, rotors, drums,
hoses and parking brake.
At Every Oil Change Interval As Indicated
By Oil Change Indicator System:
Inspect front end, and lubricate — If
equipped with serviceable fittings.
Inspect and replace the Evaporative
System Fresh Air Filter as necessary,
replacement may be more frequent if
vehicle is operated in extreme dusty
conditions.
At Every Oil Change Interval As Indicated By Oil Change Indicator System:

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SERVICING AND MAINTENANCE363
(Continued)

Inspection and service should also be performed
anytime a malfunction is observed or suspected.
Retain all receipts.
Flush and replace engine
coolant. ***

X
1. Under no circumstances should oil change intervals exceed 15,000 miles (24,000 km) or 12 months or 500 Hours, whichever comes first.
2. Under no circumstances should the engine air cleaner filter exceed 30,000 miles (48,000 km) or 24 months, whichever comes first.
3. Inspect the front and rear axle surfaces every 20,000 miles (32,000 km). If gear oil leakage is suspected, check the fluid level. If using your vehicle for police, taxi, fleet, off-road or
frequent trailer towing change the axle fluid every 20,000 miles (32,000 km).
Mileage or time passed
(whichever comes first):
7,500
15,000
22,500
30,000
37,500
45,000
52,500
60,000
67,500
75,000
82,500
90,000
97,500
105,000
112,500
120,000
127,500
135,000
142,500
150,000
Or Months: 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114
120

Or Kilometers:
12,000
24,000
36,000
48,000
60,000
72,000
84,000
96,000
108,000
120,000
132,000
144,000
156,000
168,000
180,000
192,000
204,000
216,000
228,000
240,000
WARNING!
You can be badly injured working on or
around a motor vehicle. Do only service
work for which you have the knowledge and
the right equipment. If you have any doubt
about your ability to perform a service job,
take your vehicle to a competent mechanic.

Failure to properly inspect and maintain your
vehicle could result in a component malfunc -
tion and effect vehicle handling and perfor -
mance. This could cause an accident.

WARNING! (Continued)CAUTION!

***The manufacturer highly recommends that
all cooling system service, maintenance, and
repairs be performed by an authorized dealer.
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374SERVICING AND MAINTENANCE

8. Pull the tension tether outward and reinstall the
glove compartment past the travel stops by
pushing in on the glove compartment sides.

Glove Compartment

NOTE:
Ensure the glove compartment door hinges and
glove compartment travel stops are fully
engaged.
9. Reattach the glove compartment tension tether by inserting the tether clip in the
glove compartment and sliding the clip
away from the face of the glove
compartment door.ACCESSORY DRIVE BELT INSPECTION
When inspecting accessory drive belts, small
cracks that run across ribbed surface of belt
from rib to rib, are considered normal. These
are not a reason to replace belt. However,
cracks running along a rib (not across) are not
normal. Any belt with cracks running along a rib
must be replaced. Also have the belt replaced if
it has excessive wear, frayed cords or severe
glazing.
Accessory Belt (Serpentine Belt)

Conditions that would require replacement:
Rib chunking (one or more ribs has sepa -
rated from belt body)
Rib or belt wear
Longitudinal belt cracking (cracks between
two ribs)
Belt slips
“Groove jumping" (belt does not maintain
correct position on pulley)
Belt broken (note: identify and correct
problem before new belt is installed)
Noise (objectionable squeal, squeak, or
rumble is heard or felt while drive belt is in
operation)
1 — Glove Compartment Travel Stop
2 — Glove Compartment Tension Tether
3 — Glove Compartment Door
WARNING!
Do not attempt to inspect an accessory
drive belt with vehicle running.
When working near the radiator cooling fan,
disconnect the fan motor lead. The fan is
temperature controlled and can start at any
time regardless of ignition mode. You could
be injured by the moving fan blades.

You can be badly injured working on or
around a motor vehicle. Only do service work
for which you have the knowledge and the
proper equipment. If you have any doubt
about your ability to perform a service job,
take your vehicle to a competent mechanic.

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