2020 Ram 3500 fuel cap

322STARTING AND OPERATING
Temperature sensors
SCR catalyst
UQS Sensor
Refer to “Instrument Cluster Display” in
“Getting To Know Your Instrument Panel” for
system messages and warnings.
NOTE:

Your vehicle is equipped with a DEF injection
system. You may occasionally hear an audible
clicking noise. This is normal operation.

The DEF pump will run for a period of time
after engine shutdown to purge the DEF
system. This is normal operation.
Diesel Exhaust Fluid Storage
Diesel Exhaust Fluid (DEF) is considered a very
stable product with a long shelf life. If DEF is
kept in temperatures between 10°F and 90°F
(-12°C and 32°C), it will last a minimum of one
year.
DEF is subject to freezing at the lowest
temperatures. For example, DEF may freeze at
temperatures at or below 12°F (-11°C). The
system has been designed to operate in this
environment. NOTE:
When working with DEF, it is important to know
that:
Any containers or parts that come into
contact with DEF must be DEF compatible
(plastic or stainless steel). Copper, brass,
aluminum, iron or non-stainless steel should
be avoided as they are subject to corrosion
by DEF.
If DEF is spilled, it should be wiped up
completely.
Adding Diesel Exhaust Fluid
The DEF gauge (located on the instrument
cluster) will display the level of DEF remaining in
the tank. Refer to “Instrument Cluster” and
“Instrument Cluster Descriptions” in “Getting To
Know Your Instrument Panel” for further
information.
NOTE:
Driving conditions (altitude, vehicle speed,
load, etc.) will affect the amount of DEF that
is used in your vehicle.
Another factor is that outside temperature
can affect DEF consumption. In cold condi
-
tions, 12°F (-11°C) and below, the DEF gauge needle can stay on a fixed position and
may not move for extended periods of time.
This is a normal function of the system.
There is an electric heater inside the DEF
tank that automatically works when neces
-
sary. And if the DEF supply does freeze, the
truck will operate normally until it thaws.
DEF Fill Procedure
NOTE:
Refer to “Fluids And Lubricants” in “Technical
Specifications” for the correct fluid type.

1. Remove cap from DEF tank (located on driver’s side of the vehicle or in fuel door).

Fill Locations

1 — Diesel Exhaust Fluid (DEF) Fill Location
2 — Diesel Fuel Fill Location

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STARTING AND OPERATING323
(Continued)
2. Insert DEF fill adapter/nozzle into DEF tank filler neck.
NOTE:
The DEF gauge may take up to five
seconds to update after adding a gallon
or more of Diesel Exhaust Fluid (DEF) to
the DEF tank. If you have a fault related
to the DEF system, the gauge may not
update to the new level. See an autho -
rized dealer for service.
The DEF gauge may also not immediately
update after a refill if the temperature of
the DEF fluid is below 12°F (-11°C). The
DEF line heater will possibly warm up the
DEF fluid and allow the gauge to update
after a period of run time. Under very cold
conditions, it is possible that the gauge
may not reflect the new fill level for
several drives.
Excessive overfilling of the DEF tank can
result in a MIL lamp/fault code and inac-
curate level readings. 3. Stop filling the DEF tank immediately when
any of the following happen: DEF stops
flowing from the fill bottle into the DEF tank,
DEF splashes out the filler neck, or a DEF
pump nozzle automatically shuts off.
4. Reinstall cap onto DEF tank.
Filling The Def Tank In Cold Climates
Since DEF will begin to freeze at 12°F (-11°C),
your vehicle is equipped with an automatic DEF
heating system. This allows the DEF injection
CAUTION!
To avoid DEF spillage, and possible
damage to the DEF tank from overfilling, do
not “top off” the DEF tank after filling.
DO NOT OVERFILL. DEF will freeze below
12ºF (-11ºC). The DEF system is designed
to work in temperatures below the DEF
freezing point, however, if the tank is over -
filled and freezes, the system could be
damaged.
When DEF is spilled, clean the area imme -
diately with water and use an absorbent
material to soak up the spills on the ground.
Do not attempt to start your engine if DEF is
accidentally added to the diesel fuel tank
as it can result in severe damage to your
engine, including but not limited to failure
of the fuel pump and injectors.
Never add anything other than DEF to the
tank – especially any form of hydrocarbon
such as diesel fuel, fuel system additives,
gasoline, or any other petroleum-based
product. Even a very small amount of these,
less than 100 parts per million or less than
1 oz. per 78 Gallons (295 Liters) will
contaminate the entire DEF system and will
require replacement. If owners use a
container, funnel or nozzle when refilling
the tank, it should either be new or one that
is has only been used for adding DEF.
Mopar provides an attachable nozzle with
its DEF for this purpose.
CAUTION! (Continued)
5

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324STARTING AND OPERATING
system to operate properly at temperatures
below 12°F (-11°C). If your vehicle is not in
operation for an extended period of time with
temperatures below 12°F (-11°C), the DEF in
the tank may freeze. If the tank is overfilled and
freezes, it could be damaged. Therefore, do not
overfill the DEF tank.
Extra care should be taken when filling with
portable containers to avoid overfilling. Note the
level of the DEF gauge in your instrument
cluster. You may safely add a maximum of
2 Gallons (7.5 Liters) of DEF from portable
containers when your DEF gauge is reading
½ full.
VEHICLE LOADING
GROSS VEHICLE WEIGHT RATING
(GVWR)
The GVWR is the total permissible weight of your
vehicle including driver, passengers, vehicle,
options and cargo. The label also specifies
maximum capacities of front and rear axle
systems (GAWR). Total load must be limited so
GVWR and front and rear GAWR are not
exceeded.
PAYLOAD
The payload of a vehicle is defined as the
allowable load weight a truck can carry,
including the weight of the driver, all
passengers, options and cargo.
GROSS AXLE WEIGHT RATING (GAWR)
The GAWR is the maximum permissible load on
the front and rear axles. The load must be
distributed in the cargo area so that the GAWR
of each axle is not exceeded.
Each axle GAWR is determined by the
components in the system with the lowest load
carrying capacity (axle, springs, tires or wheels).
Heavier axles or suspension components
sometimes specified by purchasers for
increased durability does not necessarily
increase the vehicle's GVWR.
TIRE SIZE
The tire size on the Vehicle Certification Label
represents the actual tire size on your vehicle.
Replacement tires must be equal to the load
capacity of this tire size.
RIM SIZE
This is the rim size that is appropriate for the tire
size listed.
INFLATION PRESSURE
This is the cold tire inflation pressure for your
vehicle for all loading conditions up to full
GAWR.
CURB WEIGHT
The curb weight of a vehicle is defined as the
total weight of the vehicle with all fluids,
including vehicle fuel, at full capacity
conditions, and with no occupants or cargo
loaded into the vehicle. The front and rear curb
weight values are determined by weighing your
vehicle on a commercial scale before any
occupants or cargo are added.
LOADING
The actual total weight and the weight of the
front and rear of your vehicle at the ground can
best be determined by weighing it when it is
loaded and ready for operation.

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IN CASE OF EMERGENCY361
F46 –10 Amp Red Upfitters Relay Coil – If Equipped
F47 ––Spare
F48 ––Spare
F49 –10 Amp Red IP Cluster / CSG
F50 –20 Amp Yellow Air Suspension Control Module – If Equipped
F51 –10 Amp RedIgnition Node Module / Keyless Ignition Node Module,
Radio Frequency Hub Module / Electric Steering Column
Lock - If Equipped
F52 –5 Amp Tan Battery Sensor
F53 –20 Amp Yellow Trailer Tow – Left Turn/Stop Lights - If Equipped
F54 –20 Amp Yellow Non Memory Adjustable Pedals - If Equipped
F55 ––Spare
F56 –10 Amp Red Fuel Vapor Blocker Valve - If Equipped
F57 –20 Amp Yellow TCM / PCM / Solenoid Trans Pressure SW (RFE Trans Only)
– If Equipped
F58 –10 Amp Red Bed Lighting (LED) – If Equipped
F60 –—Spare
F61 –10 Amp Red NH3 Sensor / PM Sensor – If Equipped
F62 –10 Amp Red Air Conditioning Clutch
F63 –20 Amp Yellow Ignition Coils / CAPS
CavityCartridge Fuse Micro Fuse Description
6

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390SERVICING AND MAINTENANCE
Inspection and service should also be
performed anytime a malfunction is observed or
suspected. Retain all receipts.
NOTE:
Using white lithium grease, lubricate the door
hinge pivot joints twice a year to prevent prema-
ture wear.
OIL CHANGE INDICATOR SYSTEM —
C
UMMINS DIESEL

Your vehicle is equipped with an engine oil
change indicator system. This system will alert
you when it is time to change your engine oil by
displaying the words “Oil Change Due” in your
instrument cluster display. The oil change
reminder will remind the owner to change the
engine oil every 15,000 miles (24,000 km) or
500 hours, whichever comes first, except for the
Chassis Cab models configured with optional
B20 capability that are using greater than 5%
levels of biodiesel, which are 12,500 miles
(20,000 km) or 400 hours, whichever comes
first. Failure to change the engine oil per the
maintenance schedule can result in internal
engine damage.
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” in “Getting To
Know Your Instrument Panel” for further
information.
Replace the engine oil and oil filter every
15,000 miles (24,000 km) or 12 months, or
sooner if prompted by the oil change indicator
system. Under no circumstances should oil
change intervals exceed 15,000 miles
(24,000 km) or 12 months, whichever comes
first.
NOTE:
Under no circumstances should oil change
intervals exceed 15,000 miles (24,000 km)
or 12 months or 500 hours, whichever
comes first.
Replace the engine oil and oil filter every
12,500 miles (20,000 km) or 400 hours,
whichever comes first when running greater
than 5% levels of biodiesel (Chassis Cab
models configured with optional B20 capa -
bility). If Chassis Cab models configured with optional
B20 capability are operated with greater than
5% levels of biodiesel, the oil change interval
must not exceed 12,500 miles (20,000 km) or
400 hours, whichever comes first under any
circumstances. See the Fuel Requirements
section for more information regarding
operation with biodiesel blend (B6-B20) fuel
meeting ASTM specification D-7467.
PERFORM SERVICE INDICATOR —
C
UMMINS DIESEL
Your vehicle will require emissions
maintenance at a set interval. To help remind
you when this maintenance is due, the
instrument cluster will display “Perform
Service”. When the “Perform Service” message
is displayed on the instrument cluster it is
necessary to have the emissions maintenance
performed. Emissions maintenance may
include replacing the Closed Crankcase
Ventilation (CCV) filter element. The procedure
for clearing and resetting the “Perform Service”
indicator message is located in the appropriate
Service Information.

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SERVICING AND MAINTENANCE399
CHECKING OIL LEVEL — GAS ENGINE

To ensure proper lubrication of your vehicle's
engine, the engine oil must be maintained at the
correct level. Check the oil level at regular
intervals, such as every fuel stop. The best time
to check the engine oil level is about five minutes
after a fully warmed up engine is shut off.

Checking the oil while the vehicle is on level
ground will improve the accuracy of the oil level
readings. Always maintain the oil level within
the SAFE zone on the dipstick. Adding one quart
of oil when the reading is at the bottom of the
SAFE zone will result in a reading at the top of
the safe zone on these engines.
CHECKING OIL LEVEL — DIESEL ENGINE

To ensure proper lubrication of your vehicle's
engine, the engine oil must be maintained at
the correct level. Check the oil level at regular
intervals. The best time to check the oil level is
before starting the engine after it has been parked overnight. When checking oil after
operating the engine, first ensure the engine is
at full operating temperature, then wait for
30 minutes after engine shutdown to check
the oil.

Engine Oil Dipstick

Checking the oil while the vehicle is on level
ground will improve the accuracy of the oil level
readings. Add oil only when the level on the
dipstick is below the “ADD” mark. The total
capacity from the ADD mark to the Full mark is
2 qts (1.9L). Never operate the engine with oil level below
the “ADD” mark or above the upper “SAFE”
mark.
ADDING WASHER FLUID
The fluid reservoir is located under the hood
and should be checked for fluid level at regular
intervals. Fill the reservoir with windshield
washer solvent only (not radiator antifreeze).
When refilling the washer fluid reservoir, take
some washer fluid and apply it to a cloth or
towel and wipe the wiper blades clean. This will
help blade performance.
To prevent freeze-up of your windshield washer
system in cold weather, select a solution or
mixture that meets or exceeds the temperature
range of your climate. This rating information
can be found on most washer fluid containers.
CAUTION!
Overfilling or underfilling will cause oil
aeration or loss of oil pressure. This could
damage your engine.
1 — ADD Range
2 — Full Mark
3 — SAFE Range
CAUTION!
Overfilling or underfilling the crankcase will
cause oil aeration or loss of oil pressure. This
could damage your engine.
7

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SERVICING AND MAINTENANCE413
switch to the off position, and leave off for at
least 30 seconds. Repeat this procedure
three times before cranking the engine.
3. Start the engine using the “Normal Starting” procedure. Refer to “Starting Procedures”
in “Starting and Operating” for further
information.
4. Once the engine starts, allow the engine to idle for a minimum of 30 seconds.
NOTE:
The engine may run rough until the air is forced
from all the fuel lines. NOTE:
A maximum blend of 5% biodiesel, meeting
ASTM specification D-975 may be used with
your Cummins diesel engine. (Chassis Cab
models not configured with B20 capability.)
A maximum blend of 20% biodiesel, meeting
ASTM specification D-7467 may be used with
your Cummins diesel engine. (Pickup models
and Chassis Cab models configured with B20
capability.)
Use of biodiesel mixture in excess of 20% can
negatively impact the fuel filter's ability to
separate water from the fuel, resulting in
high pressure fuel system corrosion or
damage.
Ethanol blends are not recommended or
approved for use with your Cummins diesel
engine.
In addition, commercially available fuel addi
-
tives are not necessary for the proper opera -
tion of your Cummins diesel engine.
INTERVENTION REGENERATION
S
TRATEGY — MESSAGE PROCESS FLOW
The Cummins diesel engine meets all
Environmental Protection Agency (EPA) Heavy
Duty Diesel Engine Emissions Standards,
resulting in one of the lowest emitting diesel
engines ever produced.
To achieve these emissions standards, your
vehicle is equipped with a state-of-the-art
engine and exhaust system. The engine and
exhaust after-treatment system work together
to achieve the EPA Heavy Duty Diesel Engine
Emissions Standards. These systems are
seamlessly integrated into your vehicle and
managed by the Cummins Powertrain Control
Module (PCM). The PCM manages engine
combustion to allow the exhaust system’s
catalyst to trap and burn Particulate Matter
(PM) pollutants, with no input or interaction on
your part.
If the engine is allowed to idle or the truck is
driven on low engine speed drive cycles for
more than two hours, the system will
automatically enter an emissions operating
mode that will increase the engine idle speed to
900 RPM (1050 RPM for Chassis Cab). While in
this mode, which is designed to help maintain
CAUTION!
Do not engage the starter motor for more
than 15 seconds at a time. Allow two minutes
between the cranking intervals.
WARNING!
Do not use alcohol or gasoline as a fuel
blending agent. They can be unstable under
certain conditions and be hazardous or
explosive when mixed with diesel fuel.
CAUTION!
Due to lack of lubricants in alcohol or
gasoline, the use of these fuels can cause
damage to the fuel system.
7

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SERVICING AND MAINTENANCE417
Under normal operating conditions, the
catalytic converter will not require
maintenance. However, it is important to keep
the engine properly tuned to ensure proper
catalyst operation and prevent possible catalyst
damage. NOTE:
Intentional tampering with emissions control
systems can result in civil penalties being
assessed against you.
In unusual situations involving grossly
malfunctioning engine operation, a scorching
odor may suggest severe and abnormal catalyst
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 CAUTION!
The catalytic converter requires the use of
unleaded fuel only. Leaded gasoline will
destroy the effectiveness of the catalyst as
an emissions control device and may seri -
ously reduce engine performance and
cause serious damage to the engine.
Damage to the catalytic converter can
result if your vehicle is not kept in proper
operating condition. In the event of engine
malfunction, particularly involving engine
misfire or other apparent loss of perfor -
mance, have your vehicle serviced
promptly. Continued operation of your
vehicle with a severe malfunction could
cause the converter to overheat, resulting
in possible damage to the converter and
vehicle.
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.7

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