2003 JEEP LIBERTY engine

On vehicles equipped with a limited-slip differen-
tial, never run the engine with one rear wheel off the
ground. The vehicle may drive through the rear
wheel remaining on the ground and cause you to
lose control of your vehicle.

If the engine stalls or you lose headway or cannot
make it to the top of a steep hill or grade, never
attempt to turn around. To do so may result in
tipping and rolling the vehicle. Always back care-
fully straight down a hill in R (Reverse) gear. Never
back down a hill in N (Neutral) using only the brake.

It is necessary to follow these steps to be certain that
the transfer case is fully in N (Neutral) before
recreational towing to prevent damage to internal
parts.
Transmission damage may occur if the automatic
transmission is shifted into P (Park) with the transfer
case in N (Neutral) and the engine running. With the
transfer case in N (Neutral) ensure that the engine is
OFF prior to shifting the transmission into P (Park)
(refer to steps7±8above).

Driving with a hot cooling system could damage
your vehicle. If the temperature gauge reads ªHº,
pull over and stop the vehicle. Idle the vehicle with
the air conditioner turned off until the pointer drops
back into the normal range. If the pointer remains on
the ªHº, and you hear continuous chimes, turn the
engine off immediately, and call for service.

Do not attempt to push or tow your vehicle to get it
started. Unburned fuel could enter the catalytic
converter and, once the engine has started, ignite and
damage the converter and vehicle.
Tow hooks are for emergency use only, to rescue a
vehicle stranded off road. Do not use tow hooks for
tow truck hookup or highway towing. You could
damage your vehicle. Tow straps are recommended
when towing the vehicle, chains may cause vehicle
damage.
WARNING!
Stand clear of vehicles when pulling with tow
hooks. Tow straps and chains may break, causing
serious injury.

3.7L Engines
MAINTAINING YOUR VEHICLE 291

Overfilling or underfilling the crankcase will cause
aeration or loss of oil pressure. This could damage
your engine.
Change Engine Oil
Road conditions as well as your kind of driving affect the
interval at which your oil should be changed. Check the
following to determine if any apply to you:
²Day or night temperatures are below 32ÉF (0ÉC)
²Stop and go driving
²Extensive engine idling
²Driving in dusty conditions
²Short trip driving of less than 10 miles (16.2 km)
²More than 50% of your driving is at sustained high
speeds during hot weather, above 90ÉF (32ÉC)
²Taxi, Police, or delivery service (commercial service)
²Trailer towing
²Off-road or desert driving
IfANYof these apply to you, then change your engine oil
at every interval shown in schedule ªBº of the ªMainte-
nance Schedulesº section of this manual.
If none of these apply to you, then change your engine oil
at every interval shown on schedule ªAº of the ªMain-
tenance Schedulesº section of this manual
NOTE:Under no circumstances should oil change in-
tervals exceed 6,000 miles (10 000 km) or 6 months
whichever comes first.
292 MAINTAINING YOUR VEHICLE

Damage to the catalytic converter can result if your
vehicle is not kept in proper operating condition. In
the event of engine malfunction, particularly involv-
ing engine misfire or other apparent loss of perfor-
mance, have your vehicle serviced promptly. Contin-
ued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and
vehicle.