2021 RAM 1500 cooling

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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SERVICING AND MAINTENANCE425
(Continued)
and through another hose to the intake
manifold of the engine. This cooling process
enables more efficient burning of fuel resulting
in fewer emissions.
To guarantee optimum performance of the
system, keep the surfaces of the charge air
cooler, condenser and radiator clean and free
of debris. Periodically check the hoses leading
to and from the charge air cooler for cracks or
loose clamps resulting in loss of pressure and
reduced engine performance.
BRAKE SYSTEM
In order to ensure brake system performance,
all brake system components should be
inspected periodically Ú page 395.
Fluid Level Check — Brake Master Cylinder
The fluid level of the brake master cylinder
should be checked whenever the vehicle is
serviced, or immediately if the brake system
warning light is on. If necessary, add fluid to
bring level within the designated marks on the
side of the reservoir of the brake master
cylinder. Be sure to clean the top of the master
cylinder area before removing cap. With disc
brakes, fluid level can be expected to fall as the
brake pads wear. Brake fluid level should be
checked when pads are replaced. If the brake
fluid is abnormally low, check the system for
leaks Úpage 478.
WARNING!
Riding the brakes can lead to brake failure
and possibly a collision. Driving with your foot
resting or riding on the brake pedal can result
in abnormally high brake temperatures,
excessive lining wear, and possible brake
damage. You would not have your full braking
capacity in an emergency.
WARNING!
Use only manufacturer's recommended
brake fluid Ú page 478. Using the wrong
type of brake fluid can severely damage
your brake system and/or impair its perfor -
mance. The proper type of brake fluid for
your vehicle is also identified on the original
factory installed hydraulic master cylinder
reservoir.
To avoid contamination from foreign matter
or moisture, use only new brake fluid or
fluid that has been in a tightly closed
container. Keep the master cylinder reser -
voir cap secured at all times. Brake fluid in
a open container absorbs moisture from
the air resulting in a lower boiling point. This
may cause it to boil unexpectedly during
hard or prolonged braking, resulting in
sudden brake failure. This could result in a
collision.
Overfilling the brake fluid reservoir can
result in spilling brake fluid on hot engine
parts, causing the brake fluid to catch fire.
Brake fluid can also damage painted and
vinyl surfaces, care should be taken to
avoid its contact with these surfaces.
Do not allow petroleum based fluid to
contaminate the brake fluid. Brake seal
components could be damaged, causing
partial or complete brake failure. This could
result in a collision.
WARNING! (Continued)
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SERVICING AND MAINTENANCE429
F06–10 Amp Red OUTPUT TO UPFITTER PDC — If Equipped
F07 ––Spare
F08 20 Amp Blue –Trailer Tow Backup
F09 –20 Amp Yellow Trailer Stop / Turn Lamp Left
F10 –20 Amp Yellow Trailer Stop / Turn Lamp Right
F11 –15 Amp Blue ID/CLEARANCE LIGHTS — If Equipped
F12 20 Amp Blue –Trailer Tow Park Lamp
F13 ––Spare
F14 –10 Amp Red AC Clutch
F15 –5 Amp Tan Intelligent Battery Sensor (IBS)
F16 ––Spare
F17 –20 Amp Yellow Air Suspension
F18 –15 Amp Blue AGS / Rear Axle Cooling Valve / Active Air Dam
F19 ––Spare
F20 –20 Amp Yellow Adjustable Pedals
F21 30 Amp Pink –Power Side Step
F22 50 Amp Red –Air Module
F23 ––Spare
F24 –20 Amp Yellow TCM SBW
F25 40 Amp Green –Exterior Lights 2
Cavity Cartridge Fuse Micro Fuse Description
8

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432SERVICING AND MAINTENANCE
Internal Power Distribution Center
The Power Distribution Center is located under
the drivers side instrument panel. This center
contains cartridge fuses, micro fuses, relays,
and circuit breakers. A description of each fuse
and component may be stamped on the inside
cover, otherwise the cavity number of each fuse
is stamped on the inside cover that corresponds
to the following chart.CAUTION!
When installing the power distribution
center cover, it is important to ensure the
cover is properly positioned and fully
latched. Failure to do so may allow water to
get into the power distribution center and
possibly result in an electrical system
failure.
When replacing a blown fuse, it is important
to use only a fuse having the correct
amperage rating. The use of a fuse with a
rating other than indicated may result in a
dangerous electrical system overload. If a
properly rated fuse continues to blow, it
indicates a problem in the circuit that must
be corrected.
CavityCartridge Fuse Micro Fuse Description
F0130 Amp Pink –Trailer Tow Receptacle
F03 –20 Amp Yellow Module Seat Heater Front (Pass)
F04 ––Spare
F05 –20 Amp Yellow Module PPU Cooling Fan
F06 ––Spare
F07 40 Amp Green –Mod CBC 3 PWR Locks
F08 ––Spare

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474TECHNICAL SPECIFICATIONS
FLUID CAPACITIES
USMetric
Fuel (Approximate)
1500 Regular Cab Shortbed/Crew Quad Cab Models 23 Gallons87 Liters
1500 Regular Cab Shortbed/Crew Quad Cab Models 26 Gallons98 Liters
1500 Regular Cab Longbed/Crew Quad Cab Models (Optional) 33 Gallons121 Liters
Engine Oil With Filter
3.6L Engine 5 Quarts4.7 Liters
5.7L Engine 7 Quarts6.6 Liters
Cooling System
3.6L Engine 13.7 Quarts13 Liters
3.6L Motor Generator Unit 1.8 Quarts1.7 Liters
5.7L Engine 18.3 Quarts17.3 Liters
Fuel (Approximate)
3.0L Turbo Diesel Engine 26 Gallons98.5 Liters
Diesel Exhaust Fluid Tank
Tradesman/Rebel Models 5.14 Gallons19.5 Liters
All Other Models 5.74 Gallons21.7 Liters
Engine Oil With Filter
3.0L Turbo Diesel Engine 8.5 Quarts8.0 Liters
Cooling System
3.0L Turbo Diesel Engine 11.6 Quarts11 Liters

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TECHNICAL SPECIFICATIONS477
(Continued)
NOTE:
If Climatized or Number 1 ULSD fuel is not avail -
able, and you are operating below 20°F (-6°C),
in sustained arctic conditions, Mopar Premium
Diesel Fuel Treatment (or equivalent) is recom -
mended to avoid gelling.
CAUTION!
Mixing of engine coolant (antifreeze) other
than specified Organic Additive Technology
(OAT) engine coolant (antifreeze), may
result in engine damage and may decrease
corrosion protection. Organic Additive
Technology (OAT) engine coolant is
different and should not be mixed with
Hybrid Organic Additive Technology (HOAT)
engine coolant (antifreeze) or any “globally
compatible” coolant (antifreeze). If a
non-OAT engine coolant (antifreeze) 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 (antifreeze) products. Do
not use additional rust inhibitors or anti-
rust products, as they may not be compat -
ible with the radiator engine coolant and
may plug the radiator.
This vehicle has not been designed for use
with propylene glycol-based engine coolant
(antifreeze). Use of propylene glycol-based
engine coolant (antifreeze) is not recom -
mended.
CAUTION! (Continued)
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484
Blind Spot Monitoring
.................................... 318Bluetooth Connecting To A Particular Mobile PhoneOr Audio Device After Pairing
................275Body Builders Guide........................................ 11Body Mechanism Lubrication........................ 418B-Pillar Location............................................. 447Brake Assist System...................................... 311Brake Control System.................................... 311Brake Fluid.......................................... 425, 478Brake System...................................... 425, 467Fluid Check............................................... 425Master Cylinder......................................... 425Parking...................................................... 151Warning Light............................................ 126Brake/Transmission Interlock....................... 155Bulb Replacement......................................... 437Bulbs, Light.......................................... 371, 437
C
Camera.......................................................... 202Camera, AUX........................................ 204, 208Camera, Rear...................................... 202, 204Camper............................................................ 97Capacities, Fuel............................................. 474Caps, FillerOil (Engine)................................................ 404Radiator (Coolant Pressure)...................... 423Car Washes................................................... 462
Carbon Monoxide Warning................... 371, 372Cargo Light....................................................... 56CD................................................................. 268Cellular Phone.............................................. 309Center High Mounted Stop Light................... 442Center Seat Storage Compartment.................. 68Charge Air Cooler.......................................... 424Chart, Tire Sizing........................................... 444Check Engine Light (Malfunction Indicator
Light)............................................................. 138Checking Your Vehicle For Safety................. 369Checks, Safety.............................................. 369Child Restraint.............................................. 355Child RestraintsBooster Seats........................................... 358Child Seat Installation..................... 364, 365How To Stow An unused ALR Seat Belt.... 363Infant And Child Restraints....................... 357Locating The LATCH Anchorages.............. 362Lower Anchors And Tethers For Children.. 360Older Children And Child Restraints......... 357Seating Positions...................................... 359Clean Air Gasoline......................................... 469CleaningWheels..................................................... 456Climate Control................................................ 60Automatic.................................................... 60Manual........................................................ 63Cold Weather Operation............................... 146
Compact Spare Tire...................................... 455Connected Services...................................... 282Connected Services FAQ............................... 301Connected Services Features....................... 286Connected Services, Getting Started............ 284Connected Services, Introduction................. 282Contract, Service........................................... 480Controls........................................................ 259Cooling Pressure Cap (Radiator Cap)............ 423Cooling System............................................. 421Adding Coolant (Antifreeze)...................... 422Coolant Level................................... 421, 423Cooling Capacity....................................... 474Disposal Of Used Coolant......................... 423Drain, Flush, And Refill............................. 422Inspection................................................. 423Points To Remember................................ 424Pressure Cap............................................ 423Radiator Cap............................................. 423Selection Of Coolant (Antifreeze)......................... 422, 474, 475Corrosion Protection..................................... 461Cruise ControlAccel/Decel.............................................. 178Cancel....................................................... 179Resume.................................................... 179Cruise Control (Speed Control)............. 177, 179Cruise Light................................................... 136Customer Assistance.................................... 479Cybersecurity................................................ 236

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