2021 RAM 1500 coolant temperature

395
SERVICING AND MAINTENANCE
SCHEDULED SERVICING — GASOLINE
ENGINE
Your vehicle is equipped with an automatic oil
change indicator system. The oil change
indicator system will remind you that it is time to
take your vehicle in for scheduled maintenance.
Based on engine operation conditions, the oil
change indicator message will illuminate. This
means that service is required for your vehicle.
Operating conditions such as frequent
short-trips, trailer tow, and extremely hot or cold
ambient temperatures will influence when the
“Oil Change Required” message is displayed.
Severe operating conditions can cause the
change oil message to illuminate as early as
3,500 miles (5,600 km) since last reset. Have
your vehicle serviced as soon as possible,
within the next 500 miles (805 km).
An authorized dealer will reset the oil change
indicator message after completing the
scheduled oil change. If a scheduled oil change
is performed by someone other than an authorized dealer, the message can be reset by
referring to the steps described under
Instrument Cluster Display Ú
page 114.
NOTE:
Under no circumstances should oil change
intervals exceed 10,000 miles (16,000 km),
12 months or 350 hours of engine run time,
whichever comes first. The 350 hours of engine
run or idle time is generally only a concern for
fleet customers.
Severe Duty All Models
NOTE:
Vehicles that are operated in a dusty and
off-road environment, or predominately at idle
or very low engine RPM are known as Severe
Duty vehicles. It is recommended that you
change the engine oil at 4,000 miles
(6,500 km) or 350 hours of engine run time.
Once A Month Or Before A Long Trip:
Check engine oil level.
Check windshield washer fluid level.
Check tire pressure and look for unusual
wear or damage. Rotate tires at the first sign
of irregular wear, even if it occurs before the
oil indicator system turns on.
Check the fluid levels of the coolant reservoir,
brake master cylinder, and fill as needed.
Check function of all interior and exterior
lights.
MAINTENANCE PLAN
Refer to the Maintenance Plan 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.
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SERVICING AND MAINTENANCE399
SCHEDULED SERVICING — DIESEL ENGINE
Your vehicle is equipped with an automatic oil
change indicator system. The oil change
indicator system will remind you that it is time to
take your vehicle in for scheduled maintenance. Based on engine operation conditions, the oil
change indicator message will illuminate. This
means that service is required for your vehicle.
Operating conditions such as frequent
short-trips, trailer tow, extremely hot or cold
ambient temperatures will influence when the
“Oil Change Required” message is displayed.
Severe Operating Conditions will cause the
change oil message to illuminate more
frequently. Have your vehicle serviced as soon
as possible, within the next 500 miles
(805 km).
An authorized dealer will reset the oil change
indicator message after completing the
scheduled oil change. If a scheduled oil change
is performed by someone other than an
authorized dealer, the message can be reset by
referring to the steps described under
Instrument Cluster Display Ú
page 114.NOTE:
Under no circumstances should oil change
intervals exceed 10,000 miles (16,000 km) or
12 months, whichever comes first.
Once A Month Or Before A Long Trip:
Check engine oil level
Check windshield washer fluid level
Check the tire inflation pressures and look
for unusual wear or damage
Check the fluid levels of the coolant reservoir,
brake master cylinder, and power steering,
and fill as needed
Check function of all interior and exterior
lights
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
malfunction and effect vehicle handling
and performance. This could cause an acci
-
dent.
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SERVICING AND MAINTENANCE421
overheating. If this occurs, stop the vehicle, turn
off the engine and allow it to cool. Service,
including a tune-up to manufacturer's
specifications, should be obtained immediately.
To minimize the possibility of catalytic converter
damage:
Do not interrupt the ignition when the trans -
mission is in gear and the vehicle is in
motion.
Do not try to start the vehicle by pushing or
towing the vehicle.
Do not idle the engine with any ignition
components disconnected or removed, such
as when diagnostic testing, or for prolonged
periods during very rough idle or malfunc -
tioning operating conditions.
COOLING SYSTEM Engine Coolant Checks
Check the engine coolant (antifreeze)
protection every 12 months (before the onset of
freezing weather, where applicable). If the
engine coolant is dirty or rusty in appearance,
the system should be drained, flushed and
refilled with fresh coolant. Check the front of the
A/C condenser (if equipped) or radiator for any
accumulation of bugs, leaves, etc. If dirty, clean
by gently spraying water from a garden hose
vertically down the face of the A/C condenser (if
equipped) or the back of the radiator core.
Check the engine cooling system hoses for
brittle rubber, cracking, tears, cuts and
tightness of the connection at the coolant
recovery bottle and radiator. Inspect the entire
system for leaks.
DO NOT REMOVE THE COOLANT PRESSURE CAP
WHEN THE COOLING SYSTEM IS HOT. 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 open a cooling system pressure
cap when the radiator or coolant bottle is
hot.
Keep hands, tools, clothing, and jewelry
away from the radiator cooling fan when
the hood is raised. The fan starts automati -
cally and may start at any time, whether the
engine is running or not.
When working near the radiator cooling fan,
disconnect the fan motor lead or turn the
ignition to the OFF mode. The fan is
temperature controlled and can start at any
time the ignition is in the ON mode.
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422SERVICING AND MAINTENANCE
Cooling System — Drain, Flush And Refill
NOTE:
Some vehicles require special tools to add
coolant properly. Failure to fill these systems
properly could lead to severe internal engine
damage. If any coolant is needed to be added to
the system please contact an authorized
dealer.
If the engine coolant (antifreeze) is dirty or
contains visible sediment, have an authorized
dealer clean and flush with OAT coolant
(conforming to MS.90032).
For the proper maintenance intervals
Úpage 395.
Selection Of Coolant
For further information Ú page 475.
NOTE:
Mixing of engine coolant (antifreeze) other
than specified Organic Additive Technology
(OAT) engine coolant, may result in engine
damage and may decrease corrosion protec-
tion. OAT engine coolant is different and
should not be mixed with Hybrid Organic
Additive Technology (HOAT) engine coolant or
any “globally compatible” coolant. If a non-OAT engine coolant is introduced into the
cooling system in an emergency, the cooling
system will need to be drained, flushed, and
refilled with fresh OAT coolant (conforming to
MS.90032), by an authorized dealer as soon
as possible.
Do not use water alone or alcohol-based
engine coolant products. Do not use addi-
tional rust inhibitors or anti-rust products, as
they may not be compatible with the radiator
engine coolant and may plug the radiator.
This vehicle has not been designed for use
with propylene glycol-based engine coolant.
Use of propylene glycol-based engine coolant
is not recommended.
Some vehicles require special tools to add
coolant properly. Failure to fill these systems
properly could lead to severe internal engine
damage. If any coolant is needed to be added
to the system please contact an authorized
dealer.
Adding Coolant
Your vehicle has been built with an improved
engine coolant (OAT coolant conforming to
MS.90032) that allows extended maintenance
intervals. This engine coolant (antifreeze) can
be used up to 10 years or 150,000 miles
(240,000 km) before replacement. To prevent
reducing this extended maintenance period, it
is important that you use the same engine
coolant (OAT coolant conforming to MS.90032)
throughout the life of your vehicle.
Please review these recommendations for
using Organic Additive Technology (OAT) engine
coolant that meets the requirements of FCA
Material Standard MS.90032. When adding
engine coolant:
We recommend using Mopar® Antifreeze/
Coolant 10 Year/150,000 Mile (240,000 km)
Formula OAT that meets the requirements of
FCA Material Standard MS.90032.
Mix a minimum solution of 50% OAT engine
coolant that meets the requirements of FCA
Material Standard MS.90032 and distilled
water. Use higher concentrations (not to
exceed 70%) if temperatures below −34°F
(−37°C) are anticipated. Please contact an
authorized dealer for assistance.
Use only high purity water such as distilled or
deionized water when mixing the water/
engine coolant solution. The use of lower
quality water will reduce the amount of corro
-
sion protection in the engine cooling system.

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SERVICING AND MAINTENANCE423
NOTE:
It is the owner's responsibility to maintain the
proper level of protection against freezing
according to the temperatures occurring in
the area where the vehicle is operated.
Some vehicles require special tools to add
coolant properly. Failure to fill these systems
properly could lead to severe internal engine
damage. If any coolant is needed to be added
to the system, please contact an authorized
dealer.
Mixing engine coolant types is not recom -
mended and can result in cooling system
damage. If HOAT and OAT coolant are mixed
in an emergency, have an authorized dealer
drain, flush, and refill with OAT coolant
(conforming to MS.90032) as soon as
possible.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss
of engine coolant (antifreeze), and to ensure
that engine coolant will return to the radiator
from the coolant expansion bottle/recovery
tank (if equipped). The cap should be inspected and cleaned if
there is any accumulation of foreign material on
the sealing surfaces.
Disposal Of Used Coolant
Used ethylene glycol-based coolant (antifreeze)
is a regulated substance requiring proper
disposal. Check with your local authorities to
determine the disposal rules for your
community. To prevent ingestion by animals or
children, do not store ethylene glycol-based
coolant in open containers or allow it to remain
in puddles on the ground, clean up any ground
spills immediately. If ingested, seek emergency
assistance immediately.
Checking Coolant Level — 3.6L Engine
The level of the coolant in the pressurized
coolant bottle should be between the “MIN” and
“MAX” range on the bottle when the engine is
cold.
The radiator normally remains completely full,
so there is no need to remove the cap unless
checking for coolant freeze point or replacing
engine coolant (antifreeze). Advise your service
attendant of this. As long as the engine
operating temperature is satisfactory, the
coolant bottle need only be checked once a
month. When additional engine coolant is
needed to maintain the proper level, it should
be added to the coolant bottle. Do not overfill.
Checking Coolant Level — 5.7L Engines
With the engine off and cold, the level of the
engine coolant should be between the ADD and
SAFE range on the dipstick.
To check the coolant level:

1. Open the coolant reservoir.

2. Lift and remove the plastic dipstick from the
reservoir neck.
WARNING!
Do not open hot engine cooling system.
Never add engine coolant (antifreeze) when
the engine is overheated. Do not loosen or
remove the cap to cool an overheated
engine. Heat causes pressure to build up in
the cooling system. To prevent scalding or
injury, do not remove the pressure cap
while the system is hot or under pressure.
Do not use a pressure cap other than the
one specified for your vehicle. Personal
injury or engine damage may result.
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424SERVICING AND MAINTENANCE

Coolant Reservoir Dipstick

3. Check the coolant level on the dipstick.
The radiator normally remains completely full,
so there is no need to remove the radiator cap
unless checking for engine coolant (antifreeze)
freeze point or replacing engine coolant. Advise
your service attendant of this. As long as the
engine operating temperature is satisfactory,
the coolant bottle need only be checked once a
month.
When additional engine coolant is needed to
maintain the proper level, it should be added to
the coolant bottle. Do not overfill.
Cooling System Notes
NOTE:
When the vehicle is stopped after a few miles/
kilometers of operation, you may observe vapor
coming from the front of the engine compart -
ment. This is normally a result of moisture from
rain, snow, or high humidity accumulating on
the radiator and being vaporized when the ther -
mostat opens, allowing hot engine coolant (anti -
freeze) to enter the radiator.
If an examination of your engine compartment
shows no evidence of radiator or hose leaks,
the vehicle may be safely driven. The vapor will
soon dissipate.
Do not overfill the coolant expansion bottle.
Check the coolant freeze point in the radiator
and in the coolant expansion bottle. If engine
coolant needs to be added, the contents of
the coolant expansion bottle must also be
protected against freezing.
If frequent engine coolant additions are
required, the cooling system should be pres -
sure tested for leaks.
Maintain engine coolant concentration at a
minimum of 50% OAT coolant (conforming to
MS.90032) and distilled water for proper
corrosion protection of your engine which
contains aluminum components.
Make sure that the coolant expansion bottle
overflow hoses are not kinked or obstructed.
Keep the front of the radiator clean. If your
vehicle is equipped with air conditioning,
keep the front of the condenser clean.
Do not change the thermostat for Summer or
Winter operation. If replacement is ever
necessary, install ONLY the correct type ther -
mostat. Other designs may result in unsatis -
factory engine cooling performance, poor gas
mileage, and increased emissions.
CHARGE AIR COOLER — INTER-COOLER
(D
IESEL ENGINE)
The charge air cooler is positioned in front of the
radiator and the air conditioner condenser. Air
enters the engine through the air cleaner and
passes through the turbocharger, where it is
pressurized. This pressurized air rapidly
reaches high temperature. The air is then
directed through a hose to the charge air cooler

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483
INDEX
A
Adaptive Cruise Control (ACC) (Cruise
Control)
................................................ 177, 179Adding Engine Coolant (Antifreeze)............... 422Adding Fuel.......................................... 208, 210Additives, Fuel............................................... 469AdjustDown........................................................... 36Forward....................................................... 36Rearward..................................................... 36Up................................................................ 36Adjustable Pedals............................................ 43Advance Phone Connectivity......................... 279Air BagAir Bag Operation...................................... 344Air Bag Warning Light...................... 342, 345Enhanced Accident Response......... 353, 394Event Data Recorder (EDR)....................... 394Front Air Bag............................................. 345If Deployment Occurs................................ 352Knee Impact Bolsters................................ 349Maintaining Your Air Bag System.............. 354Maintenance............................................. 354Redundant Air Bag Warning Light.............343Transporting Pets...................................... 369Air Bag Light............................... 126, 342, 369
Air Cleaner, Engine (Engine Air Cleaner
Filter)............................................................ 411Air Conditioner Maintenance........................ 415Air Conditioner Refrigerant........................... 415Air Conditioner System................................. 415Air Conditioning................................................ 63Air Conditioning Filter..............................67, 415Air Conditioning System................................... 65Air Conditioning, Operating Tips....................... 66Air Filter........................................................ 411Air PressureTires......................................................... 450Air Suspension..................................... 165, 169AlarmSecurity Alarm....................................26, 127Alterations/ModificationsVehicle......................................................... 11Antifreeze (Engine Coolant)................. 422, 474Disposal................................................... 423Anti-Lock Brake System (ABS)...................... 310Anti-Lock Warning Light................................ 132Assist, Hill Start............................................. 317Audio Settings............................................... 266Audio Systems (Radio).................................. 236Auto Down Power Windows............................. 78Automatic Door Locks...................................... 30
Automatic Headlights.......................................54Automatic High Beams.....................................53Automatic Tailgate Release.............................85Automatic Temperature Control (ATC)..............65Automatic Transmission....................... 156, 426Adding Fluid.............................................. 426Fluid And Filter Change............................. 426Fluid Change............................................. 426Fluid Level Check...................................... 426Fluid Type........................................ 426, 478Special Additives...................................... 426Automatic Transmission Limp Home Mode... 159AutoPark....................................................... 141AUX Camera......................................... 204, 208Auxiliary Driving Systems.............................. 318Axle Fluid.............................................. 426, 478Axle Lubrication............................................ 426
B
Back-Up......................................................... 202Back-Up Camera........................................... 202Battery................................................. 128, 409Charging System Light.............................. 128Keyless Key Fob Replacement....................18Battery Saver Feature......................................57Belts, Seat.................................................... 369
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490
Seats
................................................. 34, 35, 36Adjustment........................................... 34, 36Easy Entry................................................... 37Head Restraints.......................................... 40Memory....................................................... 32Power.......................................................... 36Rear Folding................................................ 34Reclining Rear............................................. 36Tilting.......................................................... 34Security System...................................... 26, 127Selection Of Coolant (Antifreeze)...................475Send & Go........................................... 293, 302Sentry Key (Immobilizer).................................. 20Service Assistance......................................... 479Service Contract............................................ 480Service Manuals............................................ 482Settings, Audio.............................................. 266Shifting.......................................................... 154Automatic Transmission............................ 156Transfer Case, Shifting Into Transfer Case Neutral (N)................................... 232Transfer Case, Shifting Out Of TransferCase Neutral (N)................................... 233Shoulder Belts............................................... 336Side Steps, Power............................................ 28Signals, Turn..................................55, 136, 371Sirius Satellite Radio..................................... 261Favorites................................................... 264Replay....................................................... 262
SiriusXM Satellite RadioBrowse in SXM......................................... 264Favorites................................................... 264Replay...................................................... 262Sliding Rear Window, Power............................ 79Smart Watch................................................. 300Snow Chains (Tire Chains)............................ 458Snow Plow.................................................... 227Snow Tires.................................................... 454SOS Call............................................... 286, 301Spare Tires.......................................... 455, 456Spark Plugs................................................... 475Speed Control (Cruise Control)..................... 179Starting....................................... 140, 143, 144Automatic Transmission........................... 141Button......................................................... 21Cold Weather............................................ 146Engine Fails To Start................................. 144Starting And Operating......................... 143, 144Starting Procedures............................. 143, 144Starting Procedures (Gas Engines)............... 140SteeringPower....................................................... 174Tilt Column.................................................. 31Wheel, Heated...................................... 31, 32Wheel, Tilt.................................................... 31Steering Wheel Audio Controls..................... 259Steering Wheel Mounted Sound System...... 259
Steps, Power Side............................................28Stolen Vehicle Assistance.................... 297, 303Storage............................................................68Storage Compartment, Center Seat.................68Storage, Vehicle..................................... 66, 461Store Radio Presets...................................... 265Storing Your Vehicle...................................... 461Sun Roof..................................... 80, 81, 82, 84Sunglasses Storage.........................................70Sunshade Operation........................................81SuspensionAir.................................................... 165, 169Sway Control, Trailer..................................... 318Synthetic Engine Oil...................................... 410
T
Tailgate Removal.............................................86Tailgate, Electronic Lowering...........................85Telescoping Steering Column...........................31Temperature Control, Automatic (ATC).............65TiltDown...........................................................37Up................................................................37Tilt Steering Column.........................................31Tip Start........................................................ 143Tire And Loading Information Placard........... 447Tire Markings................................................ 443Tire Safety Information.................................. 443

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