tire size RAM CHASSIS CAB 2020 Owner's Manual

386SERVICING AND MAINTENANCE
(Continued)
It is recommended to replace the two front tires
or two rear tires as a pair. Replacing just one tire
can seriously affect your vehicle’s handling. If
you ever replace a wheel, make sure that the
wheel’s specifications match those of the orig -
inal 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 replace -
ment 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.
Summer tires do not contain the all season
designation or mountain/snowflake symbol on
the tire sidewall. Use Summer tires only in sets
of four; failure to do so may adversely affect the
safety and handling of your vehicle.
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)
WARNING!
Do not use Summer tires in snow/ice
conditions. You could lose vehicle control,
resulting in severe injury or death. Driving too
fast for conditions also creates the possibility
of loss of vehicle control.

2020_RAM_CHASSIS_CAB_OM_USA=GUID-6C67832B-7839-4CCF-BEFC-CDF988F949EA=1=en=.book Page 386

SERVICING AND MAINTENANCE387
Snow Tires
Some areas of the country require the use of
snow tires during the Winter. Snow tires can be
identified by a “mountain/snowflake” symbol
on the tire sidewall.
If you need snow tires, select tires
equivalent in size and type to the orig -
inal equipment tires. Use snow tires
only in sets of four; failure to do so
may adversely affect the safety and handling of
your vehicle.
Snow tires generally have lower speed ratings
than what was originally equipped with your
vehicle and should not be operated at
sustained speeds over 75 mph (120 km/h). For
speeds above 75 mph (120 km/h) refer to orig -
inal equipment or an authorized tire dealer for
recommended safe operating speeds, loading
and cold tire inflation pressures.
While studded tires improve performance on
ice, skid and traction capability on wet or dry
surfaces may be poorer than that of
non-studded tires. Some states prohibit
studded tires; therefore, local laws should be
checked before using these tire types.
Spare Tires — If Equipped
Refer to the “Towing Requirements - Tires” in
“Starting And Operating” for restrictions when
towing with a spare tire designated for tempo -
rary emergency use.
Spare Tire Matching Original Equipped Tire
And Wheel — If Equipped
Your vehicle may be equipped with a spare tire
and wheel equivalent in look and function to the
original equipment tire and wheel found on the
front or rear axle of your vehicle. This spare tire
may be used in the tire rotation for your vehicle.
If your vehicle has this option, refer to an autho -
rized tire dealer for the recommended tire rota -
tion pattern.
Compact Spare Tire — If Equipped
The compact spare is for temporary emergency
use only. You can identify if your vehicle is
equipped with a compact spare by looking at
the spare tire description on the Tire and
Loading Information Placard located on the
driver’s side door opening or on the sidewall of
the tire. Compact spare tire descriptions begin
with the letter “T” or “S” preceding the size
designation. Example: T145/80D18 103M.
T, S = Temporary Spare Tire
Since this tire has limited tread life, the original
equipment tire should be repaired (or replaced)
and reinstalled on your vehicle at the first
opportunity.
Do not install a wheel cover or attempt to mount
a conventional tire on the compact spare wheel,
since the wheel is designed specifically for the
compact spare tire. Do not install more than
one compact spare tire and wheel on the
vehicle at any given time.CAUTION!
Because of the reduced ground clearance, do
not take your vehicle through an automatic
car wash with a compact or limited use
temporary spare installed. Damage to the
vehicle may result.
7

2020_RAM_CHASSIS_CAB_OM_USA=GUID-6C67832B-7839-4CCF-BEFC-CDF988F949EA=1=en=.book Page 387

388SERVICING AND MAINTENANCE
Collapsible Spare Tire — If Equipped
The collapsible spare is for temporary emer -
gency use only. You can identify if your vehicle is
equipped with a collapsible spare by looking at
the spare tire description on the Tire and
Loading Information Placard located on the
driver’s side door opening or on the sidewall of
the tire.
Collapsible spare tire description example:
165/80-17 101P.
Since this tire has limited tread life, the original
equipment tire should be repaired (or replaced)
and reinstalled on your vehicle at the first
opportunity. Inflate collapsible tire only after the wheel is
properly installed to the vehicle. Inflate the
collapsible tire using the electric air pump
before lowering the vehicle.
Do not install a wheel cover or attempt to mount
a conventional tire on the collapsible spare
wheel, since the wheel is designed specifically
for the collapsible spare tire.
Full Size Spare — If Equipped
The full size spare is for temporary emergency
use only. This tire may look like the originally
equipped tire on the front or rear axle of your
vehicle, but it is not. This spare tire may have
limited tread life. When the tread is worn to the
tread wear indicators, the temporary use full
size spare tire needs to be replaced. Since it is
not the same as your original equipment tire,
replace (or repair) the original equipment tire
and reinstall on the vehicle at the first opportu
-
nity.
Limited Use Spare — If Equipped
The limited use spare tire is for temporary emer -
gency use only. This tire is identified by a label
located on the limited use spare wheel. This
label contains the driving limitations for this
spare. This tire may look like the original
equipped tire on the front or rear axle of your
vehicle, but it is not. Installation of this limited
use spare tire affects vehicle handling. Since it
is not the same as your original equipment tire,
replace (or repair) the original equipment tire
and reinstall on the vehicle at the first opportu -
nity.
WARNING!
Compact and collapsible spares are for
temporary emergency use only. With these
spares, do not drive more than 50 mph
(80 km/h). Temporary use spares have
limited tread life. When the tread is worn to
the tread wear indicators, the temporary use
spare tire needs to be replaced. Be sure to
follow the warnings, which apply to your
spare. Failure to do so could result in spare
tire failure and loss of vehicle control.
WARNING!
Compact and Collapsible spares are for
temporary emergency use only. With these
spares, do not drive more than 50 mph
(80 km/h). Temporary use spares have
limited tread life. When the tread is worn to
the tread wear indicators, the temporary use
spare tire needs to be replaced. Be sure to
follow the warnings, which apply to your
spare. Failure to do so could result in spare
tire failure and loss of vehicle control.

2020_RAM_CHASSIS_CAB_OM_USA=GUID-6C67832B-7839-4CCF-BEFC-CDF988F949EA=1=en=.book Page 388

390SERVICING AND MAINTENANCE
(Continued)
Dark Vapor Chrome, Black Satin Chrome, or
Low Gloss Clear Coat Wheels
Tire Chains and Traction Devices
Use of traction devices require sufficient
tire-to-body clearance. Due to limited clearance,
the following traction devices are recom-
mended. Follow these recommendations to
guard against damage.
Traction device must be of proper size for the
tire, as recommended by the traction device
manufacturer.
No other tire sizes are recommended for use
with a tire chain or traction device. Chassis Cab 3500 (Single Rear Wheel) Models
Install on rear tires only.
For LT275/70R18E tire, use of a U-class
snow chain is recommended.
Chassis Cab 3500 4x2 (Dual Rear Wheel)
Models
Install on rear tires only.
For a LT235/80R17E tire, use of a U-class
snow chain is recommended.
Chassis Cab 3500 4x4 (Dual Rear Wheel)
Models
Install on front/rear tires.
For a LT235/80R17E tire, use of a U-class
snow chain is recommended.
Chassis Cab 4500/5500 Models
Install on rear tires only.
For a 225/70R19.5G tire, use of a U-class
snow chain is recommended.
CAUTION!
If your vehicle is equipped with these
specialty wheels, DO NOT USE wheel
cleaners, abrasives, or polishing compounds.
They will permanently damage this finish and
such damage is not covered by the New
Vehicle Limited Warranty. HAND WASH ONLY
USING MILD SOAP AND WATER WITH A SOFT
CLOTH. Used on a regular basis; this is all that
is required to maintain this finish.
WARNING!
Using tires of different size and type (M+S,
Snow) between front and rear axles can
cause unpredictable handling. You could lose
control and have a collision.
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.

2020_RAM_CHASSIS_CAB_OM_USA=GUID-6C67832B-7839-4CCF-BEFC-CDF988F949EA=1=en=.book Page 390

398TECHNICAL SPECIFICATIONS
Torque Specifications
**Use only authorized dealer recommended
lug nuts/bolts and clean or remove any dirt or
oil before tightening.
Inspect the wheel mounting surface prior to
mounting the tire and remove any corrosion or
loose particles.
NOTE:
Dual wheels are flat mounted, center piloted.
The lug nuts are a two-piece assembly. When
the tires are being rotated or replaced, clean
these lug nuts and add two drops of oil at the interface between the hex and the washer.
Ensure that the socket is fully engaged on the
lug nut/bolt (do not insert it half way).

Oil Interface Location

Do not oil wheel studs. For chrome wheels, do
not substitute with chrome plated wheel nuts.

Wheel Mounting Surface
Retighten the wheel nuts in the same sequence
to the torques listed in the table. Go through the
sequence a second time to verify that specific
torque has been achieved. Retighten to specifi
-
cations after 25 miles (40 km) and check the
lug nut/bolt torque to be sure that all the lug
nuts/bolts are properly seated against the
wheel.

8/10 Lug Nuts/Bolts Torque Patterns

It is recommended that wheel stud nuts be kept
torqued to specifications at all times. Torque
wheel stud nuts to specifications at each lubri -
cation interval.
Lug Nut/
Bolt
Torque
Lug Nut/
Bolt Type
**Lug
Nut/Bolt
SizeLug Nut/
Bolt
Socket
Size
120-150 Ft-Lbs
(160-200 N·m) Cone
M14 x 1.50 22 mm
130-160
Ft-Lbs
(190-220 N·m) Flanged
1 — 10 Bolt Pattern
2 — 8 Bolt Pattern

2020_RAM_CHASSIS_CAB_OM_USA=GUID-6C67832B-7839-4CCF-BEFC-CDF988F949EA=1=en=.book Page 398

511
Snow Chains (Tire Chains)
.......................390Snow Plow...........................................286Snow Tires...........................................387Spare Tires...................................387, 388Spark Plugs..........................................407Speed Control Accel/Decel......................................231Cancel.............................................231Resume...........................................231Speed Control (Cruise Control)..........230, 232Starting............................... 183, 184, 187Automatic Transmission............... 183, 187Button...............................................17Cold Weather....................................187Engine Block Heater...........................190Engine Fails To Start...........................186Starting And Operating............................184Starting Procedures........................184, 187Starting Procedures (Diesel Engines)..........187Starting Procedures (Gas Engines).............183SteeringPower..............................................229Tilt Column.........................................38Wheel, Heated.....................................38Wheel, Tilt..........................................38Steering Wheel Audio Controls..................481Steering Wheel Mounted Sound
System Controls....................................481Storage.................................................72Storage Compartment, Center Seat..............73
Storage, Vehicle.............................. 63, 393Storing Your Vehicle............................... 393Sunglasses Storage................................. 81Sway Control, Trailer.............................. 127Synthetic Engine Oil............................... 349
T
Telescoping Steering Column..................... 38Temperature Control, Automatic (ATC).......... 62TiltDown................................................ 31Up.................................................... 31Tilt Steering Column................................. 38Tip Start...................................... 183, 188Tire And Loading Information Placard......... 379Tire Markings....................................... 375Tire Safety Information........................... 374Tires........................... 182, 382, 387, 392Aging (Life Of Tires)............................ 385Air Pressure...................................... 382Chains............................................. 390Changing......................................... 314Compact Spare................................. 387Dual............................... 317, 391, 398General Information................... 382, 387High Speed....................................... 383Inflation Pressure............................... 383Jacking............................................ 314Life Of Tires...................................... 385Load Capacity................................... 379
Pressure Monitoring System(TPMS)................................ 113, 132Quality Grading................................. 392Radial............................................. 384Replacement.................................... 385Rotation.......................................... 391Safety..................................... 374, 382Sizes.............................................. 376Snow Tires....................................... 387Spare Tires.............................. 387, 388Spinning.......................................... 384Trailer Towing................................... 280Tread Wear Indicators......................... 385Wheel Nut Torque.............................. 397To Open Hood........................................ 66Tongue Weight/Trailer Weight.................. 279Torque Converter Clutch......................... 212Towing........................................ 274, 326Disabled Vehicle................................ 326Guide.............................................. 279Recreational..................................... 288Weight............................................ 279Towing Behind A Motorhome................... 288Traction.............................................. 292Traction Control.................................... 124Traction Control Switch........................... 124Trailer Sway Control (TSC)....................... 127Trailer Towing....................................... 274Cooling System Tips........................... 285Hitches........................................... 278
11

2020_RAM_CHASSIS_CAB_OM_USA=GUID-6C67832B-7839-4CCF-BEFC-CDF988F949EA=1=en=.book Page 511