2021 RAM CHASSIS CAB steering

SERVICING AND MAINTENANCE397
F32– –Spare
F33 20 Amp Blue –Trans Control Module – If Equipped
F34 30 Amp Pink –Vehicle System Interface Module #2 – If Equipped
F35 30 Amp Pink –Sunroof – If Equipped
F36 30 Amp Pink –Electric Back Light – If Equipped
F37 30 Amp Pink –Diesel Frame / Fuel Heater #2– If Equipped
F38 30 Amp Pink –Integrated Trailer Brake Module – If Equipped
F39 – –Spare
F40 –10 Amp Red Ventilated Seats – If Equipped
F41 –10 Amp Red Active Grille Shutter / Active Air Dam – If Equipped
F42 –20 Amp Yellow Horn
F43 –15 Amp Blue Heated Steering Wheel – If Equipped
F44 –10 Amp Red Diagnostic Port
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
Cavity Cartridge Fuse Micro Fuse Description
8

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SERVICING AND MAINTENANCE399
F74–10 Amp Red Backup Alarm – If Equipped
F75 –10 Amp Red ATMM / Coil-SCR Module RLY – If Equipped
F76 –10 Amp Red Electronic Stability Control — If Equipped
F77 –10 Amp Red Drivetrain Control Module / Front Axle Disconnect Module / TCM/ STOM
F78 –15 Amp BlueEngine Control Module / Powertrain Control Module / AEB RACM MOD /
Feed To AUX PDC Relay Coils/ HRLS
F79 –15 Amp Blue ID / Clearance Lights
F80 –10 Amp Red Overhead Console / Assist / 911 – If Equipped
F81 –20 Amp Yellow Trailer Tow Right Turn / Stop Lights - If Equipped
F82 –10 Amp Red Steering Column Control Module / Cruise Control
F83 – –Spare
F84 –15 Amp Blue ASBM / HVAC / ICS / Rear Heated Seat Switches
F85 –10 Amp Red Airbag Module
F86 –10 Amp Red Airbag Module
F87 –10 Amp RedAir Suspension / ITBM / Steering Column Control Module / MOD Gateway
CAN-C Trailer TPM
F88 –15 Amp Blue Instrument Panel Cluster
F90/F91 –20 Amp Yellow Power Outlet / Batt
Power Outlet / Acc
F92 – –Spare
F93 – –Spare
Cavity Cartridge Fuse Micro Fuse Description
8

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414SERVICING AND MAINTENANCE
TIRES — GENERAL INFORMATION
Tire Pressure
Proper tire inflation pressure is essential to the
safe and satisfactory operation of your vehicle.
Four primary areas are affected by improper tire
pressure:
Safety
Fuel Economy
Tread Wear
Ride Comfort and Vehicle Stability Safety
Both underinflation and overinflation affect the
stability of the vehicle and can produce a feeling
of sluggish response or over responsiveness in
the steering.
NOTE:
Unequal tire pressures from side to side may
cause erratic and unpredictable steering
response.
Unequal tire pressure from side to side may
cause the vehicle to drift left or right.
Fuel Economy
Underinflated tires will increase tire rolling
resistance resulting in higher fuel consumption.
Tread Wear
Improper cold tire inflation pressures can cause
abnormal wear patterns and reduced tread life,
resulting in the need for earlier tire
replacement.
Ride Comfort And Vehicle Stability
Proper tire inflation contributes to a
comfortable ride. Overinflation produces a
jarring and uncomfortable ride.
WARNING!

Overloading of your tires is dangerous.
Overloading can cause tire failure, affect
vehicle handling, and increase your stopping
distance. Use tires of the recommended load
capacity for your vehicle. Never overload them.
WARNING!
Improperly inflated tires are dangerous and
can cause collisions.
Underinflation increases tire flexing and
can result in overheating and tire failure.
Overinflation reduces a tire's ability to
cushion shock. Objects on the road and
chuckholes can cause damage that result
in tire failure.
Overinflated or underinflated tires can
affect vehicle handling and can fail
suddenly, resulting in loss of vehicle
control.
Unequal tire pressures can cause steering
problems. You could lose control of your
vehicle.
Unequal tire pressures from one side of the
vehicle to the other can cause the vehicle
to drift to the right or left.
Always drive with each tire inflated to the
recommended cold tire inflation pressure.

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418SERVICING AND MAINTENANCE
(Continued)
If you ever replace a wheel, make sure that the
wheel’s specifications match those of the
original wheels.
It is recommended you contact an authorized
tire dealer or original equipment dealer with any
questions you may have on tire specifications
or capability. Failure to use equivalent
replacement tires may adversely affect the
safety, handling, and ride of your vehicle.TIRE TYPES
All Season Tires — If Equipped
All Season tires provide traction for all seasons
(Spring, Summer, Autumn, and Winter). Traction
levels may vary between different all season
tires. All season tires can be identified by the
M+S, M&S, M/S or MS designation on the tire
sidewall. Use all season tires only in sets of four;
failure to do so may adversely affect the safety
and handling of your vehicle.
Summer Or Three Season Tires — If
Equipped
Summer tires provide traction in both wet and
dry conditions, and are not intended to be
driven in snow or on ice. If your vehicle is
equipped with Summer tires, be aware these
tires are not designed for Winter or cold driving
conditions. Install Winter tires on your vehicle
when ambient temperatures are less than 40°F
(5°C) or if roads are covered with ice or snow.
For more information, contact an authorized
dealer.
WARNING!
Do not use a tire, wheel size, load rating, or
speed rating other than that specified for
your vehicle. Some combinations of unap -
proved tires and wheels may change
suspension dimensions and performance
characteristics, resulting in changes to
steering, handling, and braking of your
vehicle. This can cause unpredictable
handling and stress to steering and
suspension components. You could lose
control and have a collision resulting in
serious injury or death. Use only the tire and
wheel sizes with load ratings approved for
your vehicle.
Never use a tire with a smaller load index or
capacity, other than what was originally
equipped on your vehicle. Using a tire with
a smaller load index could result in tire
overloading and failure. You could lose
control and have a collision.
Failure to equip your vehicle with tires
having adequate speed capability can
result in sudden tire failure and loss of
vehicle control.
CAUTION!
Replacing original tires with tires of a
different size may result in false speedometer
and odometer readings.
WARNING! (Continued)

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424SERVICING AND MAINTENANCE
(Continued)
TIRE ROTATION RECOMMENDATIONS
Tires on the front and rear axles of vehicles
operate at different loads and perform different
steering, driving, and braking functions.
For these reasons, they wear at unequal rates.
These effects can be reduced by timely rotation
of tires. The benefits of rotation are especially
worthwhile with aggressive tread designs such
as those on On/Off Road type tires. Rotation will
increase tread life, help to maintain mud, snow,
and wet traction levels, and contribute to a
smooth, quiet ride.
For the proper maintenance intervals

Ú
page 354.
More frequent rotation is permissible if desired.
The reasons for any rapid or unusual wear should be
corrected prior to rotation being performed.

Tire Rotation (Rearward Cross)

NOTE:
On Canadian vehicles only, if your vehicle is
equipped with All-Season type tires on the front
and On/Off Road type tires mounted on the
rear, do not use a front to back rotation pattern.
Instead, rotate your tires side to side at the
recommended intervals.
CAUTION!
To avoid damage to your vehicle or tires,
observe the following precautions:
Because of restricted traction device clear -
ance between tires and other suspension
components, it is important that only trac-
tion devices in good condition are used.
Broken devices can cause serious damage.
Stop the vehicle immediately if noise
occurs that could indicate device breakage.
Remove the damaged parts of the device
before further use.
Install device as tightly as possible and
then retighten after driving about 0.5 mile
(0.8 km). Autosock devices do not require
retightening.
Do not exceed 30 mph (48 km/h).
Drive cautiously and avoid severe turns and
large bumps, especially with a loaded
vehicle.
Do not drive for a prolonged period on dry
pavement.
Observe the traction device manufacturer’s
instructions on the method of installation,
operating speed, and conditions for use.
Always use the suggested operating speed
of the device manufacturer’s if it is less
than 30 mph (48 km/h).
Do not use traction devices on a compact
spare tire.
CAUTION! (Continued)

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431
TECHNICAL SPECIFICATIONS
VEHICLE IDENTIFICATION NUMBER (VIN)
The VIN is found on the left front corner of
the instrument panel, visible through the
windshield.
Vehicle Identification Number

NOTE:
It is illegal to remove or alter the VIN.
BRAKE SYSTEM
If power assist is lost for any reason (for
example, repeated brake applications with
the engine off), the brakes will still function.
However, you will experience a substantial
increase in braking effort to stop the vehicle.

If either the front or rear hydraulic system loses
normal braking capability, the remaining system
will still function with some loss of overall braking
effectiveness. This will be evident by increased
pedal travel during application, greater pedal
force required to slow or stop, and activation of
the “Brake Warning Light” and/or the “ABS
Warning Light” during brake use.

HYDRAULIC BRAKE ASSIST — IF
E
QUIPPED
The brake system power assist is provided by a
hydro-boost unit which shares fluid with the
power steering system. You may experience
some clicking or hissing noises from the
hydro-boost system during hard braking
conditions.
NOTE:
Under cold temperatures, pedal effort will be
higher than normal until the power steering fluid
reaches operating temperature.
9

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444TECHNICAL SPECIFICATIONS
CHASSIS FLUIDS AND LUBRICANTS
6.4L GASOLINE ENGINE
6.7L DIESEL ENGINE
Component Fluid, Lubricant, or Genuine Part
Automatic Transmission – Eight-SpeedUse only Mopar ZF 8&9 Speed ATF Automatic Transmission Fluid, or equivalent. Failure to use
the correct fluid may affect the function or performance of your transmission.
Automatic Transmission – Six-Speed Use only Mopar ASRC Automatic Transmission Fluid or equivalent. Failure to use the proper
fluid may affect the function or performance of your transmission.
Transfer Case We recommend you use Mopar Transfer Case Lubricant for Borg Warner 44-44 and 44-45.
Front and Rear Axle Fluid We recommend you use SAE 75W-85 HD Ram GL-5 Synthetic Axle Lubricant. Limited slip
additive is required for limited slip axles.
Brake Master Cylinder We recommend you use Mopar DOT 3 and SAE J1703.
Power Steering Reservoir
We recommend you use Mopar Power Steering Fluid +4, Mopar ATF+4 Automatic Transmission Fluid.

Component Fluid, Lubricant, or Genuine Part
Automatic TransmissionOnly use Mopar ASRC Automatic Transmission Fluid or equivalent. Failure to use the proper
fluid may affect the function or performance of your transmission.
Transfer Case We recommend you use Mopar BW44–44 Transfer Case Fluid.
Front and Rear Axle Fluid We recommend you use SAE 75W-85 HD Ram GL-5 Synthetic Axle Lubricant. Limited slip
additive is required for limited slip axles.
Brake Master Cylinder We recommend you use Mopar DOT 3 and SAE J1703.

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451
Belts, Seat
..................................................... 330Bluetooth Connecting To A Particular Mobile Phone Or Audio Device After Pairing
................262Body Builders Guide........................................ 10Body Mechanism Lubrication........................ 380B-Pillar Location............................................. 411Brake Assist System...................................... 274Brake Control System.................................... 274Brake Fluid.......................................... 387, 444Brake System...................................... 387, 431Fluid Check............................................... 387Master Cylinder......................................... 387Parking...................................................... 137Warning Light............................................ 107Brake/Transmission Interlock....................... 141Bulb Replacement......................................... 401Bulbs, Light.......................................... 332, 401
C
Cab Top Clearance Lights.............................. 405Camera.......................................................... 186Camera, AUX........................................ 188, 194Camera, Rear...................................... 186, 189Capacities, Antifreeze (Engine Coolant)......... 439Capacities, Fluid............................................ 439Caps, FillerOil (Engine)................................................ 364Power Steering.......................................... 163Radiator (Coolant Pressure)...................... 385
Car Washes................................................... 428Carbon Monoxide Warning............................ 333Cargo Light....................................................... 54CD................................................................. 255Cellular Phone.............................................. 269Center High Mounted Stop Light................... 405Center Seat Storage Compartment.................. 67Changing A Flat Tire...................................... 339Charge Air Cooler.......................................... 386Chart, Tire Sizing........................................... 407Check Engine Light (Malfunction
Indicator Light).............................................. 117Checking Your Vehicle For Safety................. 330Checks, Safety.............................................. 330Child Restraint.............................................. 312Child RestraintsBooster Seats........................................... 315Child Seat Installation..................... 323, 325How To Stow An unused ALR Seat Belt.... 322Infant And Child Restraints....................... 313Locating The LATCH Anchorages.............. 320Lower Anchors And Tethers For Children.. 317Older Children And Child Restraints......... 314Seating Positions...................................... 316Clean Air Gasoline......................................... 433CleaningWheels..................................................... 421Climate Control................................................ 58Automatic.................................................... 59Manual........................................................ 62
Cold Weather Operation................................ 122Compact Spare Tire...................................... 419Contract, Service........................................... 446Controls........................................................ 247Cooling Pressure Cap (Radiator Cap)............ 385Cooling System............................................. 383Adding Coolant (Antifreeze)...................... 384Coolant Level................................... 384, 386Cooling Capacity....................................... 439Disposal Of Used Coolant......................... 385Drain, Flush, And Refill............................. 384Inspection................................................. 386Points To Remember................................ 386Pressure Cap............................................ 385Radiator Cap............................................. 385Selection Of Coolant (Antifreeze)..... 384, 440Corrosion Protection..................................... 427Cruise Control (Speed Control)............. 164, 166Cruise Light................................................... 115Customer Assistance.................................... 445Cybersecurity................................................ 220
D
Daytime Running Lights...................................51Dealer Service............................................... 367Defroster, Rear Window...................................62Defroster, Windshield............................ 62, 331Delay (Intermittent) Wipers..............................57Deleting A Phone........................................... 262Diagnostic System, Onboard......................... 116
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