RAM 1500 2WD 2021, Owner'S Manual, Page: 150 / 496

148 STARTING AND OPERATING
NOTE:

Use of Climatized ULSD Fuel or Number
1 ULSD Fuel results in a noticeable decrease
in fuel economy.

Climatized ULSD Fuel is a blend of Number
2 ULSD and Number 1 ULSD Fuels which
reduces the temperature at which wax crys -
tals form in fuel.

The fuel grade should be clearly marked on
the pump at the fuel station.

The engine requires the use of ULSD Fuel.
Use of incorrect fuel could result in engine
and exhaust system damage
Ú
page 471.

If Climatized or diesel Number 1 ULSD Fuel is
not available, and you are operating below
(20°F/-6°C), in sustained arctic conditions,
Mopar Premium Diesel Fuel Treatment (or
equivalent) is recommended to avoid gelling
(see Fuel Operating Range Chart).
Engine Oil Usage
For the correct engine oil viscosity
Ú
page 475.
Winter Front Cover
Winter Front Cover
A Winter front or cold weather cover can be
used in ambient temperatures below 32°F
(0°C), especially during extended idle
conditions. This cover is equipped with four
flaps for managing total grille opening in varying
ambient temperatures. If a Winter front or cold
weather cover is to be used the flaps should be
in the full open position to allow air flow to the
cooling module and automatic transmission oil
cooler. When ambient temperatures drop below
0°F (-17°C) the four flaps need to be closed. A
suitable cold weather cover is available from a
Mopar dealer.
Engine Warm-Up
Avoid full throttle operation when the engine is
cold. When starting a cold engine, bring the
engine up to operating speed slowly to allow the
oil pressure to stabilize as the engine warms up.
If temperatures are below 32°F (0°C), operate
the engine at moderate speeds for five minutes
before full loads are applied.
E
NGINE
I
DLING
Avoid prolonged idling, long periods of idling
may be harmful to your engine because
combustion chamber temperatures can drop so
low that the fuel may not burn completely.
Incomplete combustion allows carbon and
varnish to form on piston rings, cylinder head
valves, and injector nozzles. Also, the unburned
fuel can enter the crankcase, diluting the oil
and causing rapid wear to the engine.
S
TOPPING
T
HE
E
NGINE
After full load operation, idle the engine for a
few minutes before shutting it down. This idle
period will allow the lubricating oil and coolant
to carry excess heat away from the
turbocharger. Refer to the following chart for
proper engine shutdown.
21_DT_OM_EN_USC_t.book Page 148