Fuel System Cautions; Fuel Requirements - Diesel Engine - Jeep Gladiator 2021 Owner's Manual

454 TECHNICAL SPECIFICATIONS
F S C
UEL YSTEM AUTIONS
CAUTION!
Follow these guidelines to maintain your
vehicle's performance:
The use of leaded gasoline is prohibited by

Federal law. Using leaded gasoline can
impair engine performance and damage
the emissions control system.
An out-of-tune engine, certain fuel or igni-

tion malfunctions can cause the catalytic
converter to overheat. If you notice a
pungent burning odor or some light smoke,
your engine may be out-of-tune or malfunc-
tioning and may require immediate service.
Contact an authorized dealer for service
assistance.
The use of fuel additives, which are now

being sold as octane enhancers, is not
recommended. Most of these products
contain high concentrations of methanol.
Fuel system damage or vehicle perfor-
mance problems resulting from the use of
such fuels or additives is not the responsi-
bility of FCA and may void or not be covered
under the New Vehicle Limited Warranty.
NOTE:
Intentional tampering with the emissions
control system can result in civil penalties being
assessed against you.
FUEL REQUIREMENTS – DIESEL ENGINE
Federal law requires that you must fuel this
vehicle with Ultra Low Sulfur Highway Diesel
fuel (15 ppm Sulfur maximum) and prohibits
the use of Low Sulfur Highway Diesel fuel
(500 ppm Sulfur maximum) to avoid damage to
the emissions control system.
Use good quality diesel fuel from a reputable
supplier in your vehicle. For most year-round
service, Number 2 diesel fuel meeting ASTM
(formerly known as the American Society for
Testing and Materials) specification D-975
Grade S15 will provide good performance. If the
vehicle is exposed to extreme cold (below 20°F
or -7°C), or is required to operate at
colder-than-normal conditions for prolonged
periods, use climatized Number 2 diesel fuel or
dilute the Number 2 diesel fuel with 50%
Number 1 diesel fuel. This will provide better
protection from fuel gelling or wax-plugging of
the fuel filters.
WARNING!
Do not use alcohol or gasoline as a fuel
blending agent. They can be unstable under
certain conditions and hazardous or
explosive when mixed with diesel fuel.
Diesel fuel is seldom completely free of water.
To prevent fuel system trouble, drain the
accumulated water from the fuel/water
separator using the fuel/water separator drain
provided on the fuel filter housing. If you buy
good quality fuel and follow the cold weather
advice above, fuel conditioners should not be
required in your vehicle. If available in your
area, a high cetane "premium" diesel fuel may
offer improved cold-starting and warm-up
performance.
CAUTION!
If the "Water in Fuel Indicator Light" remains
on, DO NOT START engine before you drain
the water from the fuel filter(s) to avoid
engine damage Ú page 398.