2016 Ram 2500 heating

Operating Precautions
Avoid Overheating The Engine
The temperature of the engine coolant (antifreeze) (a
mixture of 50% ethylene-glycol and 50% water) must not
exceed the normal range of the temperature gauge 240°F
(116°C) with a 21 psi (145 kPa) coolant pressure cap.
Usually the engine coolant (antifreeze) temperature indi-
cated during operation will be to the left of center in the
normal range of the gauge.
Avoid Low Coolant Temperature Operation
Continual operation at low engine coolant (antifreeze)
temperature below the normal range on the gauge 140°F
(60°C) can be harmful to the engine. Low engine coolant
(antifreeze) temperature can cause incomplete combus-
tion which allows carbon and varnish to form on pistonrings and injector nozzles. Also, the unburned fuel can
enter the crankcase, diluting the lubricating oil and
causing rapid wear to the engine.
Cooling System Tips — Automatic Transmission
To reduce potential for engine and transmission over-
heating in high ambient temperature conditions, take the
following actions:
•
City Driving —
When stopped, shift the transmission into NEUTRAL
and increase engine idle speed.
• Highway Driving —
Reduce your speed.
• Up Steep Hills —
Select a lower transmission gear.
• Air Conditioning —
Turn it off temporarily.
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Select (ERS) shift control (refer to “Electronic Range
Select (ERS) Operation” in this section for further infor-
mation) to select a lower gear range. Under these condi-
tions, using a lower gear range will improve performance
and extend transmission life by reducing excessive shift-
ing and heat buildup.
If the transmission temperature exceeds normal operat-
ing limits, the powertrain controller will modify the
transmission shift schedule and expand the range of
torque converter clutch engagement. This is done to
prevent transmission damage due to overheating.
If the transmission becomes extremely hot or is in danger
of overheating, the “Transmission Temperature Warning
Light” may illuminate and the transmission may operate
differently until the transmission cools down.NOTE:
Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer up a steep
grade, or in stop-and-go traffic) during hot weather. In
these conditions, torque converter slip can impose a
significant additional heat load on the cooling system.
Downshifting the transmission to the lowest possible
gear (when climbing a grade), or shifting to NEUTRAL
(when stopped in heavy traffic) can help to reduce this
excess heat generation.
During cold temperatures, transmission operation may
be modified depending on engine and transmission
temperature as well as vehicle speed. This feature im-
proves warm up time of the engine and transmission to
achieve maximum efficiency. Engagement of the torque
converter clutch is inhibited until the transmission fluid
is warm (refer to the “Note” under “Torque Converter
Clutch” in this section). On Pickup models with 68RFE
transmission, top overdrive gear is also inhibited until
the transmission fluid is warm, and during extremely
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CAUTION!
When using ERS for engine braking while descend-
ing steep grades, be careful not to overspeed the
engine. Apply the brakes as needed to prevent en-
gine overspeed.
Overdrive Operation
The automatic transmission includes an electronically
controlled Overdrive (fifth and sixth gears). The trans-
mission will automatically shift into Overdrive if the
following conditions are present:
•The shift lever is in the DRIVE position.
• The transmission fluid has reached an adequate tem-
perature.
• The engine coolant has reached an adequate tempera-
ture. •
The vehicle speed is sufficiently high.
• The driver is not heavily pressing the accelerator.
When To Use TOW/HAUL Mode
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, press the TOW/HAUL switch to activate TOW/
HAUL mode. This will improve performance and reduce
the potential for transmission overheating or failure due
to excessive shifting. When operating in TOW/HAUL
mode, transmission upshifts are delayed, and the trans-
mission will automatically downshift (for engine brak-
ing) when the throttle is closed and/or during steady
braking maneuvers.
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Filling The Def Tank In Cold Climates
Since DEF will begin to freeze at 12°F (-11°C), your
vehicle is equipped with an automatic DEF heating
system. This allows the DEF injection system to operate
properly at temperatures below 12°F (-11°C). If your
vehicle is not in operation for an extended period of time
with temperatures below 12°F (-11°C), the DEF in the
tank may freeze. If the tank is overfilled and freezes, it
could be damaged. Therefore, do not overfill the DEF
tank.
The DEF tank on these vehicles is designed with a large
amount of full reserve. So the level sensor will indicate a
Full reading even before the tank is completely full. To
put it another way, there’s additional storage capacity in
the tank above the Full mark that’s not represented in the
gauge. You may not see any movement in the reading –
even after driving up to 2,000 miles in some cases.The difference this makes varies by vehicle. Heavy-duty
pickup trucks have a 5.7-gallon tank that will display a
Full reading when about 90 percent full. This means that
drivers can consume at least 10 percent of a truly full DEF
tank without seeing any visible change in the gauge
reading. Chassis cabs have a larger 9-gallon tank, and
will display a Full reading when about 75 percent full. So
drivers can consume 25 percent of a truly full DEF tank
without seeing any visible change in the gauge reading.
Extra care should be taken when filling with portable
containers to avoid overfilling. Note the level of the DEF
gauge in your instrument cluster. On pickup applica-
tions, you may safely add a maximum of 2 gallons of DEF
from portable containers when your DEF gauge is read-
ing ½ full. On Chassis Cab applications a maximum of 2
gallons may be added when the DEF gauge is reading ¾
full.
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