2021 RAM 1500 coolant reservoir

150STARTING AND OPERATING
ENGINE BLOCK HEATER — IF EQUIPPED

Engine Block Heater Cord Location

The engine block heater warms engine coolant
and permits quicker starts in cold weather.
Connect the heater cord to a ground-fault
interrupter protected 110–115 Volt AC
electrical outlet with a grounded, three-wire
extension cord.
For diesel engines, its use is recommended for
environments that routinely fall below -10°F
(-23°C). It should be used when the vehicle has
not been running for long periods of time and
should be plugged in two hours prior to start. Its
use is required for cold starts with temperatures
under -20°F (-28°C). To ensure reliable starting at these
temperatures, use of an externally powered
electric engine block heater (available from an
authorized dealer) is recommended.
The engine block heater cord is routed under
the hood on the passenger side of the vehicle
next to the engine coolant reservoir.
ENGINE BREAK-IN RECOMMENDATIONS —
GASOLINE ENGINE
A long break-in period is not required for the
engine and drivetrain (transmission and axle) in
your vehicle.
Drive moderately during the first 300 miles
(500 km). After the initial 60 miles (100 km),
speeds up to 50 or 55 mph (80 or 90 km/h) are
desirable.
While cruising, brief full-throttle acceleration
within the limits of local traffic laws contributes
to a good break-in. Wide-open throttle
acceleration in low gear can be detrimental and
should be avoided.
The engine oil installed in the engine at the
factory is a high-quality energy conserving type
lubricant. Oil changes should be consistent with
anticipated climate conditions under which
vehicle operations will occur. For the
recommended viscosity and quality grades
Ú
page 475.
NOTE:
A new engine may consume some oil during its
first few thousand miles (kilometers) of opera -
tion. This should be considered a normal part of
the break-in and not interpreted as a problem.
Please check your oil level with the engine oil
indicator often during the break in period. Add
oil as required.
WARNING!
Remember to disconnect the engine block
heater cord before driving. Damage to the
110-115 Volt electrical cord could cause
electrocution.
CAUTION!
Never use Non-Detergent Oil or Straight
Mineral Oil in the engine or damage may
result.

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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.
8

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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.
8

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404SERVICING AND MAINTENANCE
ENGINE COMPARTMENT
3.6L ENGINE WITH STOP/START
1 — Motor Generator Unit Coolant Reservoir Pressure Cap 6 — Battery
2 — Engine Coolant Reservoir Pressure Cap 7 — Power Distribution Center (Fuses)
3 — Engine Oil Dipstick 8 — Washer Fluid Reservoir Cap
4 — Engine Oil Fill 9 — Engine Air Cleaner Filter
5 — Brake Fluid Reservoir

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SERVICING AND MAINTENANCE405
5.7L ENGINE WITHOUT STOP/START
1 — Engine Air Cleaner Filter 6 — Battery
2 — Engine Coolant Pressure Cap 7 — Power Distribution Center (Fuses)
3 — Engine Oil Fill 8 — Washer Fluid Reservoir Cap
4 — Engine Oil Dipstick 9 — Engine Coolant Reservoir Cap
5 — Brake Fluid Reservoir Cap
8

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406SERVICING AND MAINTENANCE
5.7L ENGINE WITH STOP/START
1 — Engine Air Cleaner Filter 6 — Battery
2 — Engine Coolant Pressure Cap 7 — Power Distribution Center (Fuses)
3 — Engine Oil Fill 8 — Washer Fluid Reservoir Cap
4 — Engine Oil Dipstick 9 — Engine Coolant Reservoir Cap
5 — Brake Fluid Reservoir Cap

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SERVICING AND MAINTENANCE407
3.0L DIESEL ENGINE
1 — Engine Air Cleaner Filter 5 — Brake Fluid Reservoir Cap
2 — Engine Coolant Reservoir Pressure Cap 6 — Battery
3 — Engine Oil Dipstick 7 — Power Distribution Center (Fuses)
4 — Engine Oil Fill 8 — Washer Fluid Reservoir Cap
8

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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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