2015 Ram 2500 ABS

Anti-Lock Brake System (ABS)
The Four-Wheel Anti-Lock Brake System (ABS) is de-
signed to aid the driver in maintaining vehicle control
under adverse braking conditions. The system operates
with a separate computer to modulate hydraulic pressure
to prevent wheel lockup and help avoid skidding on
slippery surfaces.
The system’s pump motor runs during an ABS stop to
provide regulated hydraulic pressure. The pump motor
makes a low humming noise during operation. This is
normal.
The ABS conducts a low-speed selftest at about 10 mph
(16 km/h). If you have your foot lightly on the brake
while this test is occurring, you may feel slight pedal
movement. The movement can be more apparent on ice
and snow. This is normal.
When you are in a severe braking condition involving
use of the ABS, you will experience some pedal drop asthe vehicle comes to a complete stop. This is the result of
the system reverting to the base brake system and is
normal.
Engagement of the ABS may be accompanied by a
pulsing sensation. You may also hear a clicking noise.
These occurrences are normal, and indicate that the
system is functioning.
WARNING!
•
Pumping of the anti-lock brakes will diminish
their effectiveness and may lead to a collision.
Pumping makes the stopping distance longer. Just
press firmly on your brake pedal when you need to
slow down or stop.
• The Anti-Lock Brake System (ABS) cannot prevent
the natural laws of physics from acting on the
vehicle, nor can it increase braking or steering
(Continued)
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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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applies optimum pressure to the brakes. The system
applies optimum pressure to the brakes in emergency
braking conditions. This can help reduce braking dis-
tances. The BAS complements the ABS. Applying the
brakes very quickly results in the best BAS assistance. To
receive the benefit of BAS, you must apply continuous
braking pressure during the stopping sequence. Do not
reduce brake pedal pressure unless braking is no longer
desired.
Once the brake pedal is released, the BAS is deactivated.
WARNING!
•The BAS cannot prevent the natural laws of phys-
ics from acting on the vehicle, nor can it increase
braking efficiency beyond that afforded by the
condition of the vehicle brakes and tires or the
traction afforded.
(Continued)
WARNING! (Continued)
•The BAS cannot prevent collisions, including those
resulting from excessive speed in turns, following
another vehicle too closely, or hydroplaning.
• The capabilities of a BAS-equipped vehicle must
never be exploited in a reckless or dangerous
manner which could jeopardize the user ’s safety or
the safety of others.
Hill Start Assist (HSA)
The HSA system is designed to assist the driver in
launching a vehicle on an incline. HSA will maintain the
level of brake pressure the driver inputs for a short
duration once the driver takes his foot off of the brake
pedal. If the driver does not apply the throttle during this
short duration, the system will release brake pressure
and the vehicle will roll down the incline. The system will
release brake pressure in proportion to the amount of
throttle applied.
578 STARTING AND OPERATING

TIRE SAFETY INFORMATION
Tire MarkingsNOTE:
•P (Passenger) — Metric tire sizing is based on U.S.
design standards. P-Metric tires have the letter “P”
molded into the sidewall preceding the size designa-
tion. Example: P215/65R15 95H.
• European — Metric tire sizing is based on European
design standards. Tires designed to this standard have
the tire size molded into the sidewall beginning with
the section width. The letter Pis absent from this tire
size designation. Example: 215/65R15 96H.
• LT (Light Truck) — Metric tire sizing is based on U.S.
design standards. The size designation for LT-Metric
tires is the same as for P-Metric tires except for the
letters “LT” that are molded into the sidewall preced-
ing the size designation. Example: LT235/85R16.
1 — U.S. DOT Safety Standards
Code (TIN) 4 — Maximum Load
2 — Size Designation 5 — Maximum Pressure
3 — Service Description 6 — Treadwear, Traction and Temperature Grades
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EXAMPLE:
Load Identification:
Absence of the following load identification symbols on the sidewall of the tire indicates a Standard Load (SL)
tire:
•XL = Extra load (or reinforced) tire, or
•LL= Light load tire or
•C, D, E, F, G = Load range associated with the maximum load a tire can carry at a specified pressure
Maximum Load – Maximum load indicates the maximum load this tire is designed to carry
Maximum Pressure – Maximum pressure indicates the maximum permissible cold tire inflation pressure for this
tire
Tire Identification Number (TIN)
The TIN may be found on one or both sides of the tire,
however, the date code may only be on one side. Tires
with white sidewalls will have the full TIN, including the
date code, located on the white sidewall side of the tire. Look for the TIN on the outboard side of black sidewall
tires as mounted on the vehicle. If the TIN is not found on
the outboard side, then you will find it on the inboard
side of the tire.
594 STARTING AND OPERATING

Rear Jacking Location
When changing a rear wheel, assemble the jack drive
tube to the jack and connect the drive tube to the
extension tube. Place the jack under the axle between the
spring and the shock absorber with the drive tubes
extending to the rear.Connect the jack tube extension and wheel wrench.
CAUTION!
Before raising the wheel off the ground, make sure
that the jack will not damage surrounding truck parts
and adjust the jack position as required.
NOTE: If the bottle jack will not lower by turning the dial
(thumbwheel) by hand, it may be necessary to use the
jack drive tube in order to lower the jack.
4. By rotating the wheel wrench clockwise, raise the vehicle until the wheel just clears the surface.
WARNING!
Raising the vehicle higher than necessary can make
the vehicle unstable and cause a collision. It could
slip off the jack and hurt someone near it. Raise the
vehicle only enough to remove the tire.
Rear Jacking Location
716 WHAT TO DO IN EMERGENCIES

Engine Air Cleaner Filter Installation
NOTE:Inspect and clean the housing if dirt or debris is
present before replacing the air filter element.
1. Install the air cleaner filter element into the housing assembly with the air cleaner filter inspection surface
facing downward.
2. Install the air cleaner cover onto the housing assembly locating tabs.
3. Latch the spring clips and lock the air cleaner cover to the housing assembly.Accessory Drive Belt Inspection
WARNING!
•Do not attempt to inspect an accessory drive belt
with vehicle running.
• When working near the radiator cooling fan, dis-
connect the fan motor lead. The fan is temperature
controlled and can start at any time regardless of
ignition switch position. You could be injured by
the moving fan blades.
• You can be badly injured working on or around a
motor vehicle. Only do service work for which you
have the knowledge and the proper equipment. If
you have any doubt about your ability to perform a
service job, take your vehicle to a competent me-
chanic.
758 MAINTAINING YOUR VEHICLE

WARNING!(Continued)
•To avoid contamination from foreign matter or
moisture, use only new brake fluid or fluid that has
been in a tightly closed container. Keep the master
cylinder reservoir cap secured at all times. Brake
fluid in a open container absorbs moisture from the
air resulting in a lower boiling point. This may
cause it to boil unexpectedly during hard or pro-
longed braking, resulting in sudden brake failure.
This could result in a collision.
• Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts, causing
the brake fluid to catch fire. Brake fluid can also
damage painted and vinyl surfaces, care should be
taken to avoid its contact with these surfaces.
(Continued)
WARNING! (Continued)
•Do not allow petroleum based fluid to contaminate
the brake fluid. Brake seal components could be
damaged, causing partial or complete brake failure.
This could result in a collision.
Rear Axle And 4x4 Front Driving Axle Fluid Level
For normal service, periodic fluid level checks are not
required. When the vehicle is serviced for other reasons
the exterior surfaces of the axle assembly should be
inspected. If gear oil leakage is suspected inspect the
fluid level. Refer to “Fluids, Lubricants, and Genuine
Parts” in “Maintaining Your Vehicle” for further informa-
tion. This inspection should be made with the vehicle in
a level position.
780 MAINTAINING YOUR VEHICLE