2015 Ram 2500 traction control

•If you experience unusual vibration after driving in
mud, slush or similar conditions, check the wheels for
impacted material. Impacted material can cause a
wheel imbalance and freeing the wheels of it will
correct the situation.
LIMITED-SLIP DIFFERENTIAL
The limited-slip differential provides additional traction
on snow, ice, mud, sand and gravel, particularly when
there is a difference between the traction characteristics
of the surface under the right and left rear wheels. During
normal driving and cornering, the limited-slip unit per-
forms similarly to a conventional differential. On slip-
pery surfaces, however, the differential delivers more of
the driving effort to the rear wheel having the better
traction.
The limited-slip differential is especially helpful during
slippery driving conditions. With both rear wheels on a
slippery surface, a slight application of the accelerator will supply maximum traction. When starting with only
one rear wheel on an excessively slippery surface, slight
momentary application of the parking brake may be
necessary to gain maximum traction.
WARNING!
On vehicles equipped with a limited-slip differential
never run the engine with one rear wheel off the
ground since the vehicle may drive through the rear
wheel remaining on the ground. You could lose
control of the vehicle.
Care should be taken to avoid sudden accelerations when
both rear wheels are on a slippery surface. This could
cause both rear wheels to spin, and allow the vehicle to
slide sideways on the crowned surface of a road or in a
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DRIVING ON SLIPPERY SURFACES
Acceleration
Rapid acceleration on snow covered, wet, or other slip-
pery surfaces may cause the driving wheels to pull
erratically to the right or left. This phenomenon occurs
when there is a difference in the surface traction under
the rear (driving) wheels.
WARNING!
Rapid acceleration on slippery surfaces is dangerous.
Unequal traction can cause sudden pulling of the rear
wheels. You could lose control of the vehicle and
possibly have a collision. Accelerate slowly and
carefully whenever there is likely to be poor traction
(ice, snow, wet mud, loose sand, etc.).
Traction
When driving on wet or slushy roads, it is possible for a
wedge of water to build up between the tire and road
surface. This is known as hydroplaning and may cause
partial or complete loss of vehicle control and stopping
ability. To reduce this possibility, the following precau-
tions should be observed:
•Slow down during rainstorms or when the roads are
slushy.
• Slow down if the road has standing water or puddles.
• Replace tires when tread wear indicators first become
visible.
• Keep tires properly inflated.
• Maintain sufficient distance between your vehicle and
the vehicle in front of you to avoid a collision in a
sudden stop.
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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 func-
tion with some loss of overall braking effectiveness. This
will be evident by increased pedal travel during applica-
tion, greater pedal force required to slow or stop, and
activation of the “Brake Warning Light” and the “ABS
Warning Light” (if equipped) during brake use.
Hydraulic Brake Assist — 2500/3500 Models Only
(Except Power Wagon)
The brake system power assist is provided by a hydro-
boost unit which shares fluid with the power steeringsystem. 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.
ELECTRONIC BRAKE CONTROL SYSTEM
Your vehicle is equipped with an advanced electronic
brake control system that includes Anti-Lock Brake Sys-
tem (ABS), Traction Control System (TCS), Brake Assist
System (BAS), Electronic Roll Mitigation (ERM), Hill
Start Assist (HSA), Electronic Stability Control (ESC),
Trailer Sway Control (TSC) and Hill Decent Control
(HDC [Power Wagon only]). All of the systems work
together to enhance vehicle stability and control in vari-
ous driving conditions, and are commonly referred to as
ESC.
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WARNING!(Continued)
efficiency beyond that afforded by the condition of
the vehicle brakes and tires or the traction afforded.
• The ABS cannot prevent collisions, including those
resulting from excessive speed in turns, following
another vehicle too closely, or hydroplaning.
• The capabilities of an ABS-equipped vehicle must
never be exploited in a reckless or dangerous
manner which could jeopardize the user’s safety or
the safety of others.
ABS Warning Light
The ABS includes an amber warning light. When the light
is illuminated, the ABS is not functioning. The system
reverts to standard, non-anti-lock brakes.
Traction Control System (TCS)
The TCS monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, brake pressure is applied to the slipping wheel(s), and engine
power is reduced to provide enhanced acceleration and
stability. A feature of the TCS system, Brake Limited
Differential (BLD), 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 torque
to be applied to the wheel that is not spinning. This
feature remains active even if TCS and ESC are in the
“Partial Off” mode. Refer to “Electronic Stability Control
(ESC)” in this section of this manual. This brake pressure
modulation transfers drive torque from slipping to non-
slipping wheels to provide optimal forward traction.
Brake Assist System (BAS)
The BAS is designed to optimize the vehicle’s braking
capability during emergency braking maneuvers. The
BAS detects an emergency braking situation by sensing
the rate and amount of brake application and then
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WARNING!
Electronic Stability Control (ESC) cannot prevent the
natural laws of physics from acting on the vehicle,
nor can it increase the traction afforded by prevailing
road conditions. ESC cannot prevent accidents, in-
cluding those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro-
planing. ESC also cannot prevent accidents resulting
from loss of vehicle control due to inappropriate
driver input for the conditions. Only a safe, attentive,
and skillful driver can prevent accidents. The capa-
bilities of an ESC equipped vehicle must never be
exploited in a reckless or dangerous manner which
could jeopardize the user ’s safety or the safety of
others.
All Two-Wheel Drive Vehicles And Four-Wheel
Drive Vehicles In 2WD, 4WD AUTO, Or 4WD
LOCK Modes Can Choose The Following ESC
Operating Modes:
ESC On
This is the normal operating mode for ESC in 2WD/4WD
AUTO/4WD LOCK modes and in 2WD vehicles. When-
ever the vehicle is started or the transfer case (if equipped)
is shifted from 4WD LOW or Neutral, back to 4WD LOCK
or 4WD AUTO, the ESC system will be in this mode. This
mode should be used for almost all driving situations. ESC
should only be turned toESC Partial Offor “ESC Full
Off” for specific reasons as noted below.
ESC Partial Off
This mode is entered by momentarily pushing the “ESC
Partial Off” switch. When in Partial Offmode, the TCS
portion of ESC, except for the “limited slip” feature
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described in the TCS section, has been disabled and the
ESC Off Indicator Lightwill be illuminated. All other
stability features of ESC function normally. This mode is
intended to be used if the vehicle is in deep snow, sand,
or gravel conditions and more wheel spin than TCS
would normally allow is required to gain traction. To
turn ESC on again, momentarily push the “ESC Off”
switch. This will restore the normal “ESC On” mode of
operation.
NOTE: To improve the vehicle’s traction when driving
with snow chains or starting off in deep snow, sand or
gravel, it may be desirable to switch to the “ESC Partial
Off” mode by pushing the “ESC Off” switch. Once the
situation requiring ESC to be switched to the “ESC Partial
Off” mode is overcome, turn ESC back on by momen-
tarily pushing the “ESC Off” switch. This may be done
while the vehicle is in motion.WARNING!
• When in “ESC Partial Off” mode, the TCS func-
tionality of ESC, (except for the limited slip feature
described in the TCS section), has been disabled
and the “ESC Off Indicator Light” will be illumi-
nated. When in “ESC Partial Off” mode, the engine
power reduction feature of TCS is disabled, and
the enhanced vehicle stability offered by the ESC
system is reduced.
• Trailer Sway Control (TSC) is disabled when the
ESC system is in the ESC Partial Offmode.
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WARNING!(Continued)
•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 read-
ings.
SUPPLEMENTAL TIRE PRESSURE INFORMATION
— IF EQUIPPED
A light load vehicle condition is defined as two passen-
gers [150 lbs (68 kg) each] plus 200 lbs (91 kg) of cargo.
Cold tire inflation pressures for a lightly loaded vehicle
will be found on the face of the driver’s door.
TIRE CHAINS (TRACTION DEVICES)
Use of traction devices require sufficient tire-to-body
clearance. Follow these recommendations to guard
against damage.
• Traction device must be of proper size for the tire, as
recommended by the traction device manufacturer.
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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 clearance be-
tween tires and other suspension components, it is
important that only traction devices in good condi-
tion 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.
(Continued)
CAUTION! (Continued)
•Install device as tightly as possible and then re-
tighten after driving about ½ mile (0.8 km).
• 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 pave-
ment.
• Observe the traction device manufacturer ’s instruc-
tions on the method of installation, operating
speed, and conditions for use. Always use the
suggested operating speed of the device manufac-
turer ’s if it is less than 30 mph (48 km/h).
• Do not use traction devices on a compact spare tire.
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