suspension Ram 1500 2018 Owner's Guide

AIR SUSPENSION SYSTEM (2500/3500 MODELS) —
IF EQUIPPED
Description
This air suspension system is a rear leveling ride height
system. The main purpose of this system is to maintain the
truck’s rear ride height level. There are two selectable
heights that can be chosen based on your operating condi-
tions.
The system requires that the ignition be in ON/RUN
position or the engine running with zero vehicle speed for
all user requested changes and load leveling.Normal Ride Height (NRH)
– This is the standard position
of the suspension and is meant for normal driving. It will
automatically adjust to maintain the rear ride height as
conditions change.
Alternate Trailer Height (ATH) – Lowers the vehicle
approximately 1 in (25 mm) for a level truck, to be used as
required while trailer towing. It will automatically adjust
to maintain the rear ride height as conditions change.
Trailer Decoupling/Unloading - The air suspension sys-
tem will load level (lower/exhaust only) for up to 10
minutes after the vehicle is turned off. This allows for easy
removal of a trailer and/or load from the back of the truck
by maintaining the ride height. After 10 minutes you will
need to turn the ignition to the run position for the air
suspension to maintain ride height. If the air suspension
system is disabled using the settings menu (Tire Jack Mode,
Transport Mode or Alignment Mode) the system will
remain disabled when the vehicle is turned off. Reactivat-
ing the air suspension can be accomplished via the settings
menu or driving the vehicle above 5 mph (8 km/h) for Tire
Jack Mode or Alignment Mode and 16 mph (26 km/h) for
Transport Mode.
Rear Leveling Ride Height Switch
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NOTE:
•Most 3500 models will not lower to Alternate Trailer
Height (ATH) when unloaded.
• Refer to “Trailer Towing” in “Starting And Operating”
for further information.
Ignition OFF Behavior
For a predetermined amount of time after the ignition is off
the air suspension may adjust to maintain a proper appear-
ance.
WARNING!
The air suspension system uses a high pressure vol-
ume of air to operate the system. To avoid personal
injury or damage to the system, see your authorized
dealer for service.
Air Suspension Modes
The air suspension system has multiple modes to protect
the system in unique situations:
Tire/Jack Mode
To assist with changing a tire, the air suspension system
has a feature which allows the automatic leveling to be disabled. This mode is intended to be enabled with engine
running. Refer to “Instrument Cluster Display” in “Getting
To Know Your Instrument Panel” or “Uconnect Settings” in
“Multimedia” if equipped with a touch screen radio for
further information.
NOTE:
This mode is intended to be enabled with engine
running.
Transport Mode
For towing your vehicle with four wheels off the road, the
air suspension system has a feature which will put the
vehicle below Normal Ride Height (NRH) and disable the
automatic load leveling system. This mode is intended to
be enabled with engine running. Refer to “Instrument
Cluster Display” in “Getting To Know Your Instrument
Panel” or “Uconnect Settings” in “Understanding Your
Instrument Panel” if equipped with a touch screen radio
for further information.
NOTE: This mode is intended to be enabled with engine
running.
Wheel Alignment Mode
Before performing a wheel alignment this mode must be
enabled. Refer to “Instrument Cluster Display” in “Getting
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STARTING AND OPERATING 357

To Know Your Instrument Panel” or “Uconnect Settings” in
“Multimedia” if equipped with a touch screen radio for
further information.
NOTE:This mode is intended to be enabled with engine
running.
Protection Strategy
In order to “protect” the air suspension system, the vehicle
will disable load leveling as required (suspension over-
loaded, battery charge low, etc.). Load leveling will auto-
matically resume as soon as system operation requirements
are met. See your authorized dealer if system does not
resume.
Instrument Cluster Display Messages
When the appropriate conditions exist, a message will
appear in the instrument cluster display. Refer to “Instru-
ment Cluster Display” in “Getting To Know Your Instru-
ment Panel” for further information.
An audible chime will be heard whenever a system error
has been detected.
See your authorized dealer for system service if normal
operation does not resume.
Operation
Pushing the Alternate Trailer Height (ATH) button once
while at Normal Ride Height (NRH), will lower the vehicle
to Alternate Trailer Height (ATH) and will illuminate the
LED.
NOTE: The LED will continuously blink until vehicle
Alternate Trailer Height (ATH) has been achieved and the
LED will turn off.
Pushing the Alternate Trailer Height (ATH) again will raise
the vehicle to Normal Ride Height (NRH).
NOTE: The LED will continuously blink until Normal Ride
Height (NRH) has been achieved.
• Transport Mode – No indicator lamps will be illumi-
nated. Transport Mode is disabled by driving the ve-
hicle.
• Tire/Jack Mode – No indicator lamps will be illumi-
nated. Tire/Jack Mode is disabled by driving the vehicle.
• Wheel Alignment Mode – No indicator lamps will be
illuminated. Wheel Alignment Mode is disabled by
driving the vehicle.
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WARNING!(Continued)
enhances vehicle stability and assists in maintaining
control of the vehicle. The system monitors vehicle
speed and will attempt to reconnect the stabilizer bar
at speeds over 18 mph (29 km/h). This is indicated by a
flashing off road light and solid on road light. Once
vehicle speed is reduced below 14 mph (22 km/h), the
system will attempt to return to the Off-Road mode.
To disconnect the stabilizer/sway bar, shift to either 4HI or
4LO as shown in “Four Wheel Drive Operation” and push
the right hand Off Road stabilizer/sway bar button to
obtain the Off-Road position. The amber indicator light
will flash until the stabilizer/sway bar has been fully
disconnected.
NOTE: The stabilizer/sway bar may be torque locked due
to left and right suspension height differences. This condi-
tion is due to driving surface differences or vehicle loading.
In order for the stabilizer/sway bar to disconnect/
reconnect, the right and left halves of the bar must be
aligned. This alignment may require that the vehicle be
driven onto level ground or rocked from side to side. To return to the On-Road mode; push the left hand On
Road stabilizer/sway bar button.
WARNING!
If the stabilizer/sway bar will not return to On-Road
mode, vehicle stability is reduced. Do not attempt to
drive the vehicle over 18 mph (29 km/h). Driving faster
than 18 mph (29 km/h) may cause loss of control of the
vehicle, which could result in serious injury or death.
Contact your local service center for assistance.
SAFE OFF-ROAD DRIVING — POWER WAGON
ONLY
Off-Road Driving Tips And Vehicle Characteristics
Your vehicle has excellent on and off-road capabilities.
These off-road capabilities will allow you to explore those
wilderness trails where few travel, providing a source of
exciting and satisfying recreation. Before you venture out,
you should contact your local governmental agency to
determine the designated off-road vehicle (ORV) trails or
recreation areas. You should always tread lightly and only
use established roads, trails or ORV recreational areas.
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After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road, it is
always a good idea to check for damage. That way you can
get any problems taken care of right away and have your
vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
• Inspect the radiator for mud and debris and clean as
required.
• Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
• Check for accumulations of plants or brush. These things
could be a fire hazard. They might hide damage to fuel
lines, brake hoses, axle pinion seals, and propeller shafts.
• After extended operation in mud, sand, water, or similar
dirty conditions, have the radiator, fan, brake rotors,
wheels, brake linings, and axle yokes inspected and
cleaned as soon as possible.
WARNING!
Abrasive material in any part of the brakes may cause
excessive wear or unpredictable braking. You might
not have full braking power when you need it to
prevent a collision. If you have been operating your
vehicle in dirty conditions, get your brakes checked
and cleaned as necessary.
• 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
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STARTING AND OPERATING 375

Gross Axle Weight Rating (GAWR)
The GAWR is the maximum permissible load on the front
and rear axles. The load must be distributed in the cargo
area so that the GAWR of each axle is not exceeded.
Each axle GAWR is determined by the components in the
system with the lowest load carrying capacity (axle,
springs, tires or wheels). Heavier axles or suspension
components sometimes specified by purchasers for in-
creased durability does not necessarily increase the vehi-
cle’s GVWR.
Tire Size
The tire size on the Vehicle Certification Label represents
the actual tire size on your vehicle. Replacement tires must
be equal to the load capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size
listed.
Inflation Pressure
This is the cold tire inflation pressure for your vehicle for
all loading conditions up to full GAWR.
Curb Weight
The curb weight of a vehicle is defined as the total weight
of the vehicle with all fluids, including vehicle fuel, at full
capacity conditions, and with no occupants or cargo loaded
into the vehicle. The front and rear curb weight values are
determined by weighing your vehicle on a commercial
scale before any occupants or cargo are added.
Loading
The actual total weight and the weight of the front and rear
of your vehicle at the ground can best be determined by
weighing it when it is loaded and ready for operation.
The entire vehicle should first be weighed on a commercial
scale to insure that the GVWR has not been exceeded. The
weight on the front and rear of the vehicle should then be
determined separately to be sure that the load is properly
distributed over the front and rear axle. Weighing the
vehicle may show that the GAWR of either the front or rear
axles has been exceeded but the total load is within the
specified GVWR. If so, weight must be shifted from front to
rear or rear to front as appropriate until the specified
weight limitations are met. Store the heavier items down
low and be sure that the weight is distributed equally. Stow
all loose items securely before driving.6
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Recommended Distribution Hitch Adjustment
Towing With 1500 Air Suspension
1. Set air suspension to normal ride height. No action isrequired if already in normal ride height.
NOTE: The vehicle must remain in the engine run position
with all doors closed while attaching a trailer for proper
leveling of the air suspension system.
2. Position the truck to be ready to connect to the trailer (do not connect the trailer).
With Weight-Distributing Hitch (Correct)Improper Adjustment Of Weight-Distributing Hitch
(Incorrect)
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STARTING AND OPERATING 419

Towing With 2500/3500 Air Suspension
1. Position the truck to be ready to connect to the trailer(do not connect the trailer).
NOTE: Normal Ride Height (NRH) or Alternate Trailer
Height (ATH) can be used. The vehicle must remain in the
engine running position while attaching a trailer for proper
leveling of the air suspension system. It may not be
possible to enter Alternate Trailer Height (ATH) while
lightly loaded.
2. Measure the height of the top of the front wheel opening on the fender to ground, this is height H1.
3. Attach the trailer to the vehicle without the weight distribution bars connected.
4. Measure the height of the top of the front wheel opening on the fender to ground, this is height H2.
5. Install and adjust the tension in the weight distributing bars per the manufacturers’ recommendations so that
the height of the front fender is approximately (H2-H1)/
2+H1 (about 1/2 the difference between H2 and H1
above normal ride height [H1]). 6. Preform a visual inspection of the trailer and weight
distributing hitch to confirm manufacturers’ recommen-
dations have been met.
Measurement Example Example 2500/3500
Height (mm)
H1 1030
H2 1058
H2-H1 28
(H2-H1)/2 14
(H2-H1)/2 + H1 1044
NOTE: For all towing conditions, we recommend towing
with tow haul mode engaged.
Towing With All Other 1500/2500/3500 (Non-Air Suspen-
sion)
1. Position the truck to be ready to connect to the trailer (do not connect the trailer).
2. Measure the height of the top of the front wheel opening on the fender to ground, this is height H1.
3. Attach the trailer to the vehicle without the weight distribution bars connected.
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STARTING AND OPERATING 421

frequent trailer towing.Refer to the “Maintenance Plan”
for the proper maintenance intervals.
NOTE: Check the automatic transmission fluid level be-
fore towing (6-speed automatic only).
Tow/Haul Mode
To reduce potential for automatic transmission overheat-
ing, activate TOW/HAUL mode when driving in hilly
areas, or select a lower gear range (using the Electronic
Range Select (ERS) shift control) on more severe grades.
Speed Control — If Equipped
• Do not use on hilly terrain or with heavy loads.
• When using the speed control, if you experience speed
drops greater than 10 mph (16 km/h), disengage until
you can get back to cruising speed.
• Use speed control in flat terrain and with light loads to
maximize fuel efficiency.
Cooling System
To reduce potential for engine and transmission overheat-
ing, take the following actions:
•City Driving
• In city traffic — while stopped, place the transmission in
NEUTRAL, but do not increase engine idle speed.
• Highway Driving
• Reduce speed.
• Air Conditioning
• Turn off temporarily.
Air Suspension System
To aid in attaching/detaching the trailer from the vehicle,
the air suspension system can be used. Refer to “Air
Suspension System” in “Starting And Operating” for fur-
ther information.
NOTE: The vehicle must remain in the engine running
position while attaching a trailer for proper leveling of the
air suspension system.
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RECREATIONAL TOWING (BEHIND MOTORHOME, ETC.)
Towing This Vehicle Behind Another Vehicle
Towing Condition Wheels OFFThe GroundTwo-Wheel
Drive Models Four-Wheel Drive Models
Flat Tow NONENOT
ALLOWED See Instructions
•
Automatic transmission in PARK
• Manual transmission in gear
(NOT in NEUTRAL)
• Transfer case in NEUTRAL (N)
• Tow in forward direction
Dolly Tow FrontNOT
ALLOWED NOT ALLOWED
Rear OK NOT ALLOWED
On Trailer ALLOK OK
NOTE:
• When towing your vehicle, always follow applicable
state and provincial laws. Contact state and provincial
Highway Safety offices for additional details.
• Vehicles equipped with air suspension must be placed in
Transport mode before tying them down (from the
body) on a trailer or flatbed truck. Refer to “Air Suspen-
sion – If Equipped” for more information. If the vehicle cannot be placed in Transport mode (for example, en-
gine will not run), tie-downs must be fastened to the
axles (not to the body). Failure to follow these instruc-
tions may cause fault codes to be set and/or cause loss
of proper tie-down tension.
436 STARTING AND OPERATING