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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 weightvalues 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 commer-
cial 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. Weigh-
ing 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
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![Ram 2500 2016 Owners Manual 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 Ram 2500 2016 Owners Manual 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](/manual-img/34/12563/w960_12563-711.png)
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 trans-
mission fluid and filter(s) as specified forpolice, taxi,
fleet, or frequent trailer towing. Refer to the “Mainte-
nance Schedule” for the proper maintenance intervals.
NOTE: Check the automatic transmission fluid level
before 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.
Electronic Speed Control — If Equipped
• Do not use in 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 over-
heating, take the following actions:
City Driving
When stopped for short periods of time, shift the trans-
mission into NEUTRAL and increase engine idle speed.
Highway Driving
Reduce speed.
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4. Connect the opposite end of the negative(-)jumper
cable to a good engine ground (exposed metal part of
the discharged vehicle’s engine) away from the battery
and the fuel injection system.
WARNING!
Do not connect the jumper cable to the negative (-)
post of the discharged battery. The resulting electri-
cal spark could cause the battery to explode and
could result in personal injury. Only use the specific
ground point, do not use any other exposed metal
parts.
5. Start the engine in the vehicle that has the booster battery, let the engine idle a few minutes, and then
start the engine in the vehicle with the discharged
battery.
CAUTION!
Do not connect jumper cable to any of the fuses on
the positive battery terminal. The resulting electrical
current will blow the fuse.
6. Once the engine is started, remove the jumper cables in the reverse sequence:
Disconnecting The Jumper Cables
1. Disconnect the negative (-)end of the jumper cable
from the engine ground of the vehicle with the dis-
charged battery.
2. Disconnect the opposite end of the negative (-)jumper
cable from the negative (-)post of the booster battery.
3. Disconnect the positive (+)end of the jumper cable
from the positive (+)post of the booster battery.
774 WHAT TO DO IN EMERGENCIES
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MAINTAINING YOUR VEHICLE
CONTENTS
ENGINE COMPARTMENT — 3.6L ..........790
ENGINE COMPARTMENT — 5.7L ..........791
ENGINE COMPARTMENT — 6.4L ..........792
ONBOARD DIAGNOSTIC SYSTEM (OBD II) . . .793
▫ Onboard Diagnostic System (OBD II)
Cybersecurity ....................... .793
▫ Loose Fuel Filler Cap Message ............794
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS ......................... .795
REPLACEMENT PARTS ..................796
DEALER SERVICE ..................... .797
MAINTENANCE PROCEDURES ...........797
▫ Engine Oil ......................... .798
▫ Engine Oil Filter ..................... .802
▫ Engine Air Cleaner Filter ................802
▫ Accessory Drive Belt Inspection ...........806
▫ Maintenance-Free Battery ...............808
▫ Air Conditioner Maintenance .............809
▫ Front Driveshaft Lubrication — 2500/3500
(Four-Wheel Drive Models Only) ..........810
7
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ONBOARD DIAGNOSTIC SYSTEM (OBD II)
Your vehicle is equipped with a sophisticated onboard
diagnostic system called OBD II. This system monitors
the performance of the emissions, engine, and automatic
transmission control systems. When these systems are
operating properly, your vehicle will provide excellent
performance and fuel economy, as well as engine emis-
sions well within current government regulations.
If any of these systems require service, the OBD II system
will turn on the “Malfunction Indicator Light (MIL).” It
will also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be drivable and not
need towing, see your authorized dealer for service as
soon as possible.
CAUTION!
•Prolonged driving with the MIL on could cause
further damage to the emission control system. It
could also affect fuel economy and driveability.
The vehicle must be serviced before any emissions
tests can be performed.
• If the MIL is flashing, while the engine is running,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.
Onboard Diagnostic System (OBD II)
Cybersecurity
Your vehicle is required to have an Onboard Diagnostic
system (OBD II) and a connection port to allow access to
information related to the performance of your emissions
controls. Authorized service technicians may need to
7
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access this information to assist with the diagnosis and
service of your vehicle and emissions system.
WARNING!
•ONLY an authorized service technician should con-
nect equipment to the OBD II connection port in
order to diagnose or service your vehicle.
• If unauthorized equipment is connected to the
OBD II connection port, such as a driver-behavior
tracking device, it may:
• Be possible that vehicle systems, including
safety related systems, could be impaired or a
loss of vehicle control could occur that may result
in an accident involving serious injury or death.
• Access, or allow others to access, information
stored in your vehicle systems, including per-
sonal information. For further information, refer to “Privacy Practices — If
Equipped With Uconnect 8.4 Radio” and “Uconnect
CyberSecurity” in “All About Uconnect Access” in your
Owner ’s Manual Radio Supplement and “Cybersecurity”
in “Understanding Your Instrument Panel” in your Own-
er ’s Manual on the DVD.
Loose Fuel Filler Cap Message
If the vehicle diagnostic system determines
that the fuel filler cap is loose, improperly
installed, or damaged, a loose gascap indicator
will display in the EVIC/DID telltale display
area. Refer to “Electronic Vehicle Information Center
(EVIC)” or “Driver Information Display (DID)” in “Un-
derstanding Your Instrument Panel” for further informa-
tion. Tighten the fuel filler cap properly and push the
794 MAINTAINING YOUR VEHICLE
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SELECT button to turn off the message. If the problem
continues, the message will appear the next time the
vehicle is started.
A loose, improperly installed, or damaged fuel filler cap
may also turn on the Malfunction Indicator Light (MIL).
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of your vehicle’s emissions control system.
Failure to pass could prevent vehicle registration.For states that require an Inspection and Mainte-
nance (I/M), this check verifies the “Malfunction
Indicator Light (MIL)” is functioning and is not
on when the engine is running, and that the OBD II
system is ready for testing.
Normally, the OBD II system will be ready. The OBD II
system may notbe ready if your vehicle was recently serviced, recently had a dead battery or a battery replace-
ment. If the OBD II system should be determined not
ready for the I/M test, your vehicle may fail the test.
Your vehicle has a simple ignition actuated test, which
you can use prior to going to the test station. To check if
your vehicle’s OBD II system is ready, you must do the
following:
1. Cycle the ignition switch to the ON position, but do
not crank or start the engine.
NOTE: If you crank or start the engine, you will have to
start this test over.
2. As soon as you cycle the ignition switch to the ON position, you will see the “Malfunction Indicator Light
(MIL)” symbol come on as part of a normal bulb
check.
7
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CAUTION!(Continued)
•Your vehicle has been built with improved fluids
that protect the performance and durability of your
vehicle and also allow extended maintenance inter-
vals. Do not use chemical flushes in these compo-
nents as the chemicals can damage your engine,
transmission, or air conditioning. Such damage is
not covered by the New Vehicle Limited Warranty.
If a flush is needed because of component malfunc-
tion, use only the specified fluid for the flushing
procedure.
Engine Oil
Checking Oil Level
To assure proper lubrication of your vehicle’s engine, the
engine oil must be maintained at the correct level. Check
the oil level at regular intervals, such as every fuel stop.
The best time to check the engine oil level is about five
minutes after a fully warmed up engine is shut off.
Checking the oil while the vehicle is on level ground will
improve the accuracy of the oil level readings. Always
maintain the oil level within the SAFE zone on the
dipstick. Adding one quart of oil when the reading is at
the bottom of the SAFE zone will result in a reading at the
top of the safe zone on these engines.
798 MAINTAINING YOUR VEHICLE