towing RAM CHASSIS CAB 2021 Service Manual

280SAFETY
(Continued)
Hill Start Assist (HSA)
HSA is designed to mitigate roll back from a
complete stop while on an incline. If the driver
releases the brake while stopped on an incline,
HSA will continue to hold the brake pressure for
a short period. If the driver does not apply the
throttle before this time expires, the system will
release brake pressure and the vehicle will roll
down the hill as normal.
The following conditions must be met in order
for HSA to activate:
The feature must be enabled.
The vehicle must be stopped.
The parking brake must be off.
The driver door must be closed.
The vehicle must be on a sufficient grade.
The gear selection must match vehicle uphill
direction (i.e., vehicle facing uphill is in
forward gear; vehicle backing uphill is in
REVERSE gear).

HSA will work in REVERSE gear and all forward
gears. The system will not activate if the trans-
mission is in PARK or NEUTRAL. For vehicles
equipped with a manual transmission, if the
clutch is pressed, HSA will remain active.
Disabling And Enabling HSA
This feature can be turned on or turned off. To
change the current setting, proceed as follows:

If disabling HSA using your instrument cluster
display, see
Ú
page 90 for further information.

If disabling HSA using Uconnect Settings, see
Úpage 228 for further information.
Towing With HSA
HSA will also provide assistance to mitigate roll
back while towing a trailer.
WARNING!

There may be situations where the Hill Start
Assist (HSA) will not activate and slight rolling
may occur, such as on minor hills or with a
loaded vehicle, or while pulling a trailer. HSA is
not a substitute for active driving involvement.
It is always the driver’s responsibility to be
attentive to distance to other vehicles, people,
and objects, and most importantly brake
operation to ensure safe operation of the
vehicle under all road conditions. Your
complete attention is always required while
driving to maintain safe control of your vehicle.
Failure to follow these warnings can result in a
collision or serious personal injury.

WARNING!

If you use a trailer brake controller with your
trailer, the trailer brakes may be activated
and deactivated with the brake switch. If so,
there may not be enough brake pressure to
hold both the vehicle and the trailer on a hill
when the brake pedal is released. In order to
avoid rolling down an incline while resuming
acceleration, manually activate the trailer
brake or apply more vehicle brake pressure
prior to releasing the brake pedal.

21_DPF_OM_EN_USC_t.book Page 280

SAFETY281
Traction Control System (TCS)
TCS monitors the amount of wheel spin of each
of the driven wheels. If wheel spin is detected,
the TCS may apply brake pressure to the
spinning wheel(s) and/or reduce engine power
to provide enhanced acceleration and stability.
A feature of the TCS, Brake Limited Differential
(BLD), functions similarly to a limited slip
differential and controls the wheel spin across a
driven axle. If one wheel on a driven axle is
spinning faster than the other, the system will
apply the brake of the spinning wheel. This will
allow more engine power to be applied to the
wheel that is not spinning. BLD may remain
enabled even if TCS and Electronic Stability
Control (ESC) are in reduced modes.
Trailer Sway Control (TSC)
TSC uses sensors in the vehicle to recognize an
excessively swaying trailer and will take the
appropriate actions to attempt to stop the sway.
NOTE:
TSC cannot stop all trailers from swaying.
Always use caution when towing a trailer and
follow the trailer tongue weight recommenda -
tions Ú page 200.
When TSC is functioning, the ESC Activation/
Malfunction Indicator Light will flash, the engine
power may be reduced and you may feel the
brakes being applied to individual wheels to
attempt to stop the trailer from swaying. TSC is
disabled when the ESC system is in the “Partial
Off” or “Full Off” modes.
AUXILIARY DRIVING SYSTEMS
FORWARD COLLISION WARNING (FCW)
W
ITH MITIGATION — IF EQUIPPED
FCW with Mitigation provides the driver with
audible warnings, visual warnings (within the
instrument cluster display), and may apply a
brake jerk to warn the driver when it detects a
potential frontal collision. The warnings and
limited braking are intended to provide the
driver with enough time to react, avoid or
mitigate the potential collision.
NOTE:
FCW monitors the information from the forward
looking sensors as well as the Electronic Brake
Controller (EBC), to calculate the probability of a
forward collision. When the system determines
that a forward collision is probable, the driver
will be provided with audible and visual warn-
ings as well as a possible brake jerk warning.
If the driver does not take action based upon
these progressive warnings, then the system
will provide a limited level of active braking to
help slow the vehicle and mitigate the potential
forward collision. If the driver reacts to the warn -
ings by braking and the system determines that
HSA is not a parking brake. Always apply
the parking brake fully when exiting your
vehicle. Also, be certain to place the trans -
mission in PARK.
Failure to follow these warnings can result
in a collision or serious personal injury.
WARNING! (Continued)
WARNING!
If TSC activates while driving, slow the vehicle
down, stop at the nearest safe location, and
adjust the trailer load to eliminate trailer
sway.
6

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IN CASE OF EMERGENCY343
(Continued)
Wheel Nuts

All wheel nuts should be tightened occasionally
to eliminate the possibility of wheel studs being
sheared or the bolt holes in the wheels becoming
elongated. This is especially important during the
first few hundred miles/kilometers of operation
to allow the wheel nuts to become properly set.
All wheel nuts should first be firmly seated
against the wheel. The wheel nuts should then
be tightened to recommended torque. Tighten
the wheel nuts to final torque in increments.
Progress around the bolt circle, tightening the
wheel nut opposite to the wheel nut just
previously tightened until final torque is achieved

Ú
page 432.

TO STOW THE FLAT OR SPARE — IF
E
QUIPPED
Refer to Upfitters Body Builder’s Guide for
information on stowing your spare tire
(if equipped).
HUB CAPS/WHEEL COVERS — IF
E
QUIPPED
The hub caps must be removed before raising
the vehicle off the ground. For 3500 Single Rear-Wheel (SRW) models, use
the flat end of the lug wrench to hook and pull
off the hub cap. Find the opening in the hub cap,
insert the lug wrench, and pull off the cap. If you
need to pry against the wheel, protect the wheel
surface.

Lug Wrench Insertion Location — Hub Cap
On 3500 models with Dual Rear-Wheels (DRW),
you must first remove the hub caps—use the
procedure noted for the single rear wheel. For
the wheel covers (wheel skins), insert the flat
end of the lug wrench between the outer edge
of the wheel cover and the wheel. Pry against
the wheel to remove the wheel cover. Repeat
this procedure around the wheel until the cover
pops off.

Lug Wrench Insertion Location — Wheel Cover

CAUTION!

Use extreme caution when removing the front and
rear wheel covers. Damage can occur to the
center cap and/or the wheel if screwdriver type
tools are used. A pulling motion, not a pry off
motion, is recommended to remove the caps.

CAUTION!
Use a pulling motion to remove the hub
cap. Do not use a twisting motion when
removing the hub cap, damage to the hub
cap; finish may occur.
7

21_DPF_OM_EN_USC_t.book Page 343

350IN CASE OF EMERGENCY
TOWING A DISABLED VEHICLE
This section describes procedures for towing a disabled vehicle using a commercial towing service. If the transmission and drivetrain are operable,
disabled vehicles may also be towed as described Ú page 215.
Proper towing or lifting equipment is required to
prevent damage to your vehicle. Use only tow
bars and other equipment designed for this
purpose, following equipment manufacturer’s
instructions. Use of safety chains is mandatory.
Attach a tow bar or other towing device to main
structural members of the vehicle, not to
fascia/bumpers or associated brackets. State
and local laws regarding vehicles under tow
must be observed. If you must use the accessories (wipers,
defrosters, etc.) while being towed, the ignition
must be in the ON/RUN mode, not the ACC
mode.
If the key fob is unavailable or the vehicle's
battery is discharged, Ú
page 348.
Towing Condition
Wheels OFF The
Ground 2WD Models
4WD Models
Flat Tow NONEIf transmission is operable:

• Transmission in NEUTRAL
• 30 mph (48 km/h) max speed
• 15 miles (24 km) max distance (6–speed transmission)
• 30 miles (48 km) max distance (8–speed transmission) Detailed instructions Ú
page 215
• Auto Transmission in PARK
• Transfer Case in NEUTRAL
• Tow in forward direction
Wheel Lift Or Dolly Tow Front
NOT ALLOWED
Rear OK NOT ALLOWED
Flatbed ALL BEST METHOD BEST METHOD
CAUTION!
Do not use sling type equipment when
towing. Vehicle damage may occur.
When securing the vehicle to a flat bed
truck, do not attach to front or rear suspen-
sion components. Damage to your vehicle
may result from improper towing.

21_DPF_OM_EN_USC_t.book Page 350

IN CASE OF EMERGENCY351
TWO-WHEEL DRIVE MODELS
FCA US LLC recommends towing your vehicle
with all four wheels OFF the ground using a
flatbed.
If flatbed equipment is not available, and the
transmission is operable, the vehicle may be
towed (with the rear wheels on the ground)
under the following conditions:
The transmission must be in NEUTRAL
Ú page 348.
The towing speed must not exceed 30 mph
(48 km/h).
The towing distance must not exceed
15 miles (24 km) for 6–speed transmission,
or 30 miles (48 km) for 8–speed transmis -
sion.
If the transmission is not operable, or the
vehicle must be towed faster than 30 mph
(48 km/h) or farther than 15 miles (24 km) for
6–speed transmission, or 30 miles (48 km) for 8–speed transmission, tow with the rear wheels
OFF the ground. Acceptable methods are to tow
the vehicle on a flatbed, or with the front wheels raised and the rear wheels on a towing dolly, or
(when using a suitable steering wheel stabilizer
to hold the front wheels in the straight position)
with rear wheels raised and the front wheels
ON
the ground.FOUR-WHEEL DRIVE MODELS

FCA US LLC recommends towing with all wheels
OFF the ground. Acceptable methods are to tow
the vehicle on a flatbed or with one end of vehicle
raised and the opposite end on a towing dolly.

If flatbed equipment is not available, and the
transfer case is operable, the vehicle may be
towed (in the forward direction, with ALL wheels
on the ground), IF the transfer case is in
NEUTRAL and the transmission is in PARK
Ú page 215.
CAUTION!
Towing this vehicle in violation of the above
requirements can cause severe engine and/
or transmission damage. Damage from
improper towing is not covered under the New
Vehicle Limited Warranty.
CAUTION!
Front or rear wheel lifts must not be used
(if the remaining wheels are on the ground).
Internal damage to the transmission or
transfer case will occur if a front or rear
wheel lift is used when towing.
Towing this vehicle in violation of the above
requirements can cause severe transmis -
sion and/or transfer case damage.
Damage from improper towing is not
covered under the New Vehicle Limited
Warranty.
7

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352IN CASE OF EMERGENCY
EMERGENCY TOW HOOKS — IF
E
QUIPPED
Your vehicle may be equipped with emergency
tow hooks.

Emergency Tow Hooks

NOTE:
For off-road recovery, it is recommended to use
both of the front tow hooks to minimize the risk
of damage to the vehicle.
ENHANCED ACCIDENT RESPONSE
SYSTEM (EARS)
This vehicle is equipped with an Enhanced
Accident Response System.
This feature is a communication network
that takes effect in the event of an impact
Ú page 310.
EVENT DATA RECORDER (EDR)
This vehicle is equipped with an event data
recorder (EDR). The main purpose of an EDR is
to record data that will assist in understanding
how a vehicle’s systems performed under
certain crash or near crash-like situations, such
as an air bag deployment or hitting a road
obstacle Ú page 311.
WARNING!
Do not use a chain for freeing a stuck
vehicle. Chains may break, causing serious
injury or death.
Stand clear of vehicles when pulling with
tow hooks. Tow straps may become disen -
gaged, causing serious injury.
CAUTION!

Tow hooks are for emergency use only, to
rescue a vehicle stranded off-road. Do not use
tow hooks for tow truck hookup or highway
towing. You could damage your vehicle.

21_DPF_OM_EN_USC_t.book Page 352

SERVICING AND MAINTENANCE355
Mileage or time passed (whichever comes first)
20,000
30,000
40,000
50,000
60,000
70,000
80,000
90,000
100,000
110,000
120,000
130,000
140,000
150,000
Or Years: 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Or Kilometers:
32,000
48,000
64,000
80,000
96,000
112,000
128,000
144,000
160,000
176,000
192,000
208,000
224,000
240,000
Additional Inspections
Inspect the CV/Universal joints. X X X X X X X X X X X X X X
Inspect front suspension, tie rod ends, and replace if necessary. X X X X X X X
Inspect the front and rear axle surfaces. If gear oil leakage is
suspected, check the fluid level. If using your vehicle for police,
taxi, fleet, off-road or frequent trailer towing, change axle fluid. X X X X X X X
Inspect the brake linings, parking brake function. X X X X X X X
Additional Maintenance
Replace the cabin air filter. X X X X X X X
Replace the engine air cleaner filter. XXXXX
Replace spark plugs.
1X
Flush and replace the engine coolant at 10 years or
150,000 miles (240,000 km) whichever comes first. X
X

Change the automatic transmission fluid (AS66RC Transmission Only).
XXX
8

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356SERVICING AND MAINTENANCE
(Continued)
Change the automatic transmission fluid and sump filter
(AS66RC Transmission Only). X
X
Inspect the transfer case fluid, change for any of the following:
police, taxi, fleet, or frequent trailer towing. X
XXXX
Change the transfer case fluid. X
Inspect and replace PCV valve if necessary. X
1. The spark plug change interval is mileage based only, yearly intervals do not apply.
Mileage or time passed (whichever comes first)
20,000
30,000
40,000
50,000
60,000
70,000
80,000
90,000
100,000
110,000
120,000
130,000
140,000
150,000
Or Years: 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Or Kilometers:
32,000
48,000
64,000
80,000
96,000
112,000
128,000
144,000
160,000
176,000
192,000
208,000
224,000
240,000
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 malfunc -
tion and effect vehicle handling and perfor -
mance. This could cause an accident.

WARNING! (Continued)

21_DPF_OM_EN_USC_t.book Page 356

SERVICING AND MAINTENANCE361
Replace the engine fuel filter. X X X X X X X X X X
Replace the chassis mounted
fuel filter. X X X X X X X X X
X
Inspect the front and rear axle
surfaces. If gear oil leakage is
suspected, check the fluid
level. If using your vehicle for
police, taxi, fleet, off-road or
frequent trailer towing change
the axle fluid.
3
Inspect the transfer case fluid
(4x4), change for any of the
following: police, taxi, fleet, or
frequent trailer towing. X
XXX X
Change the transfer case fluid
(4x4). X
X
Mileage or time passed
(whichever comes first):
7,500
15,000
22,500
30,000
37,500
45,000
52,500
60,000
67,500
75,000
82,500
90,000
97,500
105,000
112,500
120,000
127,500
135,000
142,500
150,000
Or Months: 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114
120

Or Kilometers:
12,000
24,000
36,000
48,000
60,000
72,000
84,000
96,000
108,000
120,000
132,000
144,000
156,000
168,000
180,000
192,000
204,000
216,000
228,000
240,000
8

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SERVICING AND MAINTENANCE363
(Continued)

Inspection and service should also be performed
anytime a malfunction is observed or suspected.
Retain all receipts.
Flush and replace engine
coolant. ***

X
1. Under no circumstances should oil change intervals exceed 15,000 miles (24,000 km) or 12 months or 500 Hours, whichever comes first.
2. Under no circumstances should the engine air cleaner filter exceed 30,000 miles (48,000 km) or 24 months, whichever comes first.
3. Inspect the front and rear axle surfaces every 20,000 miles (32,000 km). If gear oil leakage is suspected, check the fluid level. If using your vehicle for police, taxi, fleet, off-road or
frequent trailer towing change the axle fluid every 20,000 miles (32,000 km).
Mileage or time passed
(whichever comes first):
7,500
15,000
22,500
30,000
37,500
45,000
52,500
60,000
67,500
75,000
82,500
90,000
97,500
105,000
112,500
120,000
127,500
135,000
142,500
150,000
Or Months: 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114
120

Or Kilometers:
12,000
24,000
36,000
48,000
60,000
72,000
84,000
96,000
108,000
120,000
132,000
144,000
156,000
168,000
180,000
192,000
204,000
216,000
228,000
240,000
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 malfunc -
tion and effect vehicle handling and perfor -
mance. This could cause an accident.

WARNING! (Continued)CAUTION!

***The manufacturer highly recommends that
all cooling system service, maintenance, and
repairs be performed by an authorized dealer.
8

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