gear ratio Ram 2500 2018 Owner's Guide

Towing Tips
Before setting out on a trip, practice turning, stopping, and
backing up the trailer in an area located away from heavy
traffic.
Automatic Transmission
The DRIVE range can be selected when towing. The
transmission controls include a drive strategy to avoid
frequent shifting when towing. However, if frequent shift-
ing does occur while in DRIVE, select TOW/HAUL mode
or select a lower gear range (using the Electronic Range
Select (ERS) shift control).
NOTE:Using TOW/HAUL mode or selecting a lower
gear range (using the ERS shift control) while operating the
vehicle under heavy loading conditions will improve per-
formance and extend transmission life by reducing exces-
sive shifting and heat build up. This action will also
provide better engine braking.
When towing a loaded trailer up steep grades at low
speeds (20 mph [32 km/h] or below), holding your vehicle
in first gear (using the ERS shift control) can help to avoid
transmission overheating.
If you regularly tow a trailer for more than 45 minutes of
continuous operation, then change the automatic transmis-
sion fluid and filter(s) as specified for police, taxi, fleet, or
Seven-Pin Connector
1 — Battery5 — Ground
2 — Backup Lamps 6 — Left Stop/Turn
3 — Right Stop/Turn 7 — Running Lamps
4 — Electric Brakes
6
STARTING AND OPERATING 431

NOTE:When shifting out of transfer case NEUTRAL (N),
turning the engine OFF is not required, but may be helpful
to avoid gear clash. With the 8-speed automatic transmis-
sion, the engine must remain running, since turning the
engine OFF will shift the transmission to PARK (and the
transmission must be in NEUTRAL for the transfer case to
shift out of NEUTRAL).
5. Turn the engine OFF. Shift automatic transmission into PARK. On 8-speed transmissions the shifter will auto-
matically select PARK when the engine is turned off.
6. Release the brake pedal (and clutch pedal on a manual transmission).
7. Disconnect vehicle from the tow vehicle.
8. Start the engine.
9. Press and hold the brake pedal.
10. Release the parking brake.
11. Shift the transmission into gear, release the brake pedal (and clutch pedal on manual transmissions), and check
that the vehicle operates normally. NOTE:
With electronic shift transfer case:
• Steps 3 and 4 are requirements that must be met before
pushing the button to shift out of NEUTRAL (N), and
must continue to be met until the shift has been com-
pleted. If any of these requirements are not met before
pushing the button or are no longer met during the shift,
the NEUTRAL (N) indicator light will flash continu-
ously until all requirements are met or until the button is
released.
• The ignition must be in the ON/RUN mode for a shift to
take place and for the position indicator lights to be
operable. If the ignition is not in the ON/RUN mode, the
shift will not take place and no position indicator lights
will be on or flashing.
• A flashing NEUTRAL (N) position indicator light indi-
cates that shift requirements have not been met.
DRIVING TIPS
Driving On Slippery Surfaces
Acceleration
Rapid acceleration on snow covered, wet, or other slippery
surfaces may cause the driving wheels to pull erratically to
the right or left. This phenomenon occurs when there is a
6
STARTING AND OPERATING 441

IN CASE OF EMERGENCY
CONTENTS
HAZARD WARNING FLASHERS ............447
 ASSIST AND SOS MIRROR — IF EQUIPPED . . . .447
 BULB REPLACEMENT ....................452
▫ Replacement Bulbs .....................452
▫ Replacing Exterior Bulbs ..................454
 FUSES ............................... .461
▫ Power Distribution Center ................461
 JACKING AND TIRE CHANGING ...........468
▫ Jacking And Tire Changing 1500 Series Trucks . .468
▫ Jacking And Tire Changing 2500 And 3500 Series
Trucks ............................. .485
JUMP STARTING ........................502
▫ Preparations For Jump Start ...............502
▫ Jump Starting Procedure ..................504
 IF YOUR ENGINE OVERHEATS .............505
 GEAR SELECTOR OVERRIDE — 6-SPEED
TRANSMISSION ........................506
▫ Column Gear Selector — If Equipped .........506
▫ Center Console Gear Selector — If Equipped . . .507
 MANUAL PARK RELEASE — 8 SPEED
TRANSMISSION ........................508
 FREEING A STUCK VEHICLE ..............509
7

CAUTION!(Continued)
the event of engine malfunction, particularly involv-
ing engine misfire or other apparent loss of perfor-
mance, have your vehicle serviced promptly. Contin-
ued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and
vehicle.
Under normal operating conditions, the catalytic converter
will not require maintenance. However, it is important to
keep the engine properly tuned to assure proper catalyst
operation and prevent possible catalyst damage.
NOTE: Intentional tampering with emissions control sys-
tems can result in civil penalties being assessed against
you.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may suggest severe and
abnormal catalyst overheating. If this occurs, stop the
vehicle, turn off the engine and allow it to cool. Service,
including a tune-up to manufacturer’s specifications,
should be obtained immediately. To minimize the possibility of catalytic converter damage:
•
Do not interrupt the ignition when the transmission is in
gear and the vehicle is in motion.
• Do not try to start the vehicle by pushing or towing the
vehicle.
• Do not idle the engine with any ignition components
disconnected or removed, such as when diagnostic
testing, or for prolonged periods during very rough idle
or malfunctioning operating conditions.
Cooling System
WARNING!
You or others can be badly burned by hot engine
coolant (antifreeze) or steam from your radiator. If you
see or hear steam coming from under the hood, do not
open the hood until the radiator has had time to cool.
Never try to open a cooling system pressure cap when
the radiator is hot.
Engine Coolant Checks
Check the engine coolant (antifreeze) protection every 12
months (before the onset of freezing weather, where appli-
cable). If the engine coolant (antifreeze) is dirty or rusty in
546 SERVICING AND MAINTENANCE

NOTE:The presence of water in the gear lubricant will
result in corrosion and possible failure of differential
components. Operation of the vehicle in water, as may be
encountered in some off-highway types of service, will
require draining and refilling the axle to avoid damage.
Limited-Slip Differentials
1500 Model rear axles equipped with a Limited Slip
Differential require that 5 oz. (148 ml) Mopar Limited Slip
Additive be added to the gear lubricant. Refer to “Fluids
And Lubricants” in “Technical Specification” for further
information. The Mopar Limited Slip Additive should be
added to the gear lubricant whenever a fluid change is
made to an axle equipped with a Limited Slip Differential.
2500/3500 Model axles DO NOT REQUIREany limited
slip oil additive (friction modifiers).
NOTE: When refilling an axle with a Limited Slip Differ-
ential, (which requires a Limited Slip Additive), the Lim-
ited Slip Additive should be added before the gear lubri-
cant is added to insure proper additive fill.
Drain And Refill
Refer to the “Maintenance Plan” for the proper mainte-
nance intervals.
Transfer Case
Selection Of Lubricant
Use only the manufacturer’s recommended fluid. Refer to
“Fluids And Lubricants” in “Technical Specifications” for
further information.
Fluid Level Check
This fluid level can be checked by removing the filler plug.
The fluid level should be to the bottom edge of the filler
plug hole with the vehicle in a level position.
Drain And Refill
Refer to the “Maintenance Plan” for the proper mainte-
nance intervals.8
SERVICING AND MAINTENANCE 557