2018 Ram 2500 suspension

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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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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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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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.
432 STARTING AND OPERATING

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

Recreational Towing — Two-Wheel Drive Models
DO NOT flat tow this vehicle. Damage to the drivetrain
will result.
Recreational towing (for two-wheel drive models) is al-
lowedONLY if the rear wheels are OFFthe ground. This
may be accomplished using a tow dolly or vehicle trailer. If
using a tow dolly, follow this procedure:
NOTE: If vehicle is equipped with air suspension, ensure
the vehicle is set to Normal Ride Height.
1. Properly secure the dolly to the tow vehicle, following the dolly manufacturer’s instructions.
2. Drive the rear wheels onto the tow dolly.
3. Firmly apply the parking brake. Place automatic trans- mission in PARK, manual transmission in gear (not in
NEUTRAL).
4. Properly secure the rear wheels to the dolly, following the dolly manufacturer’s instructions.
5. Turn the ignition OFF and remove the key fob.
6. Install a suitable clamping device, designed for towing, to secure the front wheels in the straight position.
CAUTION!
•Towing with the rear wheels on the ground will
cause severe transmission damage. Damage from
improper towing is not covered under the New
Vehicle Limited Warranty.
• Do not disconnect the driveshaft because fluid may
leak from the transmission, causing damage to inter-
nal parts.
Recreational Towing — Four-Wheel Drive Models
NOTE: Both the manual shift and electronic shift transfer
cases must be shifted into NEUTRAL (N) for recreational
towing. Automatic transmissions must be shifted into
PARK for recreational towing. Manual transmissions must
be placed in gear (NOT in NEUTRAL) for recreational
towing. Refer to the following for the proper transfer case
NEUTRAL (N) shifting procedure for your vehicle.
CAUTION!
• DO NOT dolly tow any 4WD vehicle. Towing with
only one set of wheels on the ground (front or rear)
will cause severe transmission and/or transfer case
(Continued)
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STARTING AND OPERATING 437

1. Bring the vehicle to a complete stop on level ground,with the engine running. Firmly apply the parking
brake.
2. Shift the transmission to NEUTRAL.
NOTE: If vehicle is equipped with air suspension, ensure
the vehicle is set to Normal Ride Height.
3. Press and hold the brake pedal.
4. Depress the clutch pedal on a manual transmission.
5. Shift the transfer case into NEUTRAL:
•With manual shift transfer case, shift the transfer case
lever into NEUTRAL (N)
• With electronic shift transfer case, push and hold the
transfer case NEUTRAL (N) button. Some models
have a small, recessed “N” button (at the center of the
transfer case switches) that must be pushed using a
ballpoint pen or similar object. Other models have a
rectangular NEUTRAL switch, below the rotary trans-
fer case control knob. The NEUTRAL (N) indicator
light will blink while the shift is in progress. The light
will stop blinking (stay on solid) when the shift to
NEUTRAL (N) is complete. After the shift is completed
and the NEUTRAL (N) light stays on, release the
NEUTRAL (N) button. 6. Release the parking brake.
7. Shift the transmission into REVERSE.
8. Release the brake pedal (and clutch pedal on manual
transmissions) for five seconds and ensure that there is
no vehicle movement.
9. Repeat steps 7 and 8 with automatic transmission in DRIVE or manual transmission in first gear.
10. Shift the transmission to NEUTRAL. Firmly apply the parking brake. Turn OFF the engine. For vehicles with
Keyless Enter-N-Go, push and hold the ENGINE
START/STOP button until the engine shuts off.
11. Shift the transmission into PARK or place manual transmission in gear (NOT in Neutral). On 8-speed
transmissions the shifter will automatically select
PARK when the engine is turned off.
12. Turn the ignition to the OFF mode, then cycle the ignition to the RUN mode and back to the OFF mode.
Remove the key fob from the ignition.
13. Attach the vehicle to the tow vehicle using a suitable tow bar.
14. Release the parking brake.
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