2018 JEEP GRAND CHEROKEE LIMITED Owners Manual

Exhaust System
The best protection against carbon monoxide entry into the
vehicle body is a properly maintained engine exhaust sys-
tem.
If you notice a change in the sound of the exhaust system;
or if the exhaust fumes can be detected inside the vehicle;
or when the underside or rear of the vehicle is damaged;
have an authorized technician inspect the complete ex-
haust system and adjacent body areas for broken, dam-
aged, deteriorated, or mispositioned parts. Open seams or
loose connections could permit exhaust fumes to seep into
the passenger compartment. In addition, have the exhaust
system inspected each time the vehicle is raised for lubri-
cation or oil change. Replace as required.

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

•Mixing engine coolant (antifreeze) types is not recom-
mended and can result in cooling system damage. If
HOAT and OAT coolant are mixed in an emergency, have
a authorized dealer drain, flush, and refill with OAT
coolant (conforming to MS.90032) as soon as possible.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of engine
coolant (antifreeze), and to ensure that engine coolant
(antifreeze) will return to the radiator from the coolant
expansion bottle/recovery tank if so equipped.
The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.