2004 JEEP GRAND CHEROKEE oil temperature

7. Oil Pressure Gage
Indicates the engine oil pressure. This gage does
not measure oil level. Pressure varies with engine
speed, temperature, and oil viscosity. Normal oil pressure
will be midway between the lowest and highest limit
marks.
8. Sentry Key Indicator Light Ð If Equipped
Refer to ªSentry Key Immobilizer Systemº in
Section 2 of this manual for more information.
9. Malfunction Indicator Light
This light is part of an onboard diagnostic system
called OBD II which monitors engine and auto-
matic transmission control systems. This light
will illuminate when the ignition is in the ON position
before engine start. If the bulb does not come on when
turning the ignition key from OFF to ON, have the
condition checked promptly.Certain conditions such has a loose or missing gas cap,
poor fuel quality, etc. may illuminate the light after
engine start. The vehicle should be serviced if the light
stays on through several typical driving cycles. In most
situations, the vehicle will drive normally and will not
require towing.
When the engine is running, the ªMalfunction Indicator
Lightº may flash to alert of serious conditions that could
lead to immediate loss of power or severe catalytic
converter damage. The vehicle should be serviced as
soon as possible if this occurs.
10. Cruise Indicator Light
This indicator lights when the electronic speed
control system is turned ON.
11. Check Gages Warning Light
This light illuminates when the voltmeter, oil
pressure, or temperature gages indicate a reading
130 UNDERSTANDING YOUR INSTRUMENT PANEL

either too high or too low. Examine the gages carefully,
and follow the instructions above for each indicated
problem.
NOTE:When the ignition switch is turned to OFF, the
fuel gage, voltmeter, oil pressure, and temperature gages
will not show any readings. When the engine is not
running, turn the ignition switch to ON to obtain accu-
rate readings.
12. Part Time Indicator Light
This light alerts the driver that the vehicle is in
the PART TIME four±wheel drive mode, and
the front and rear driveshafts are mechanically
locked together forcing the front and rear wheels to rotate
at the same speed.
13. Transmission Over Temperature Warning Light
This light indicates that there is excessive transmis-
sion fluid temperature that might occur with severe
usage such as trailer towing or snow plowing. If this lightcomes on, stop the vehicle and run the engine at idle or
faster, with the transmission in N (Neutral) until the light
goes off.
14. Temperature Gage
Indicates engine coolant temperature. Any read-
ing within the normal range indicates that the
cooling system is operating satisfactorily.
The gage pointer will likely indicate a higher temperature
(above center scale) when driving in hot weather, up
mountain grades, or when towing a trailer. It should not
be allowed to exceed the upper limits of the normal
operating range.
If the pointer rises to the 260É (Hot) mark, pull over and
stop the vehicle. Do not turn the engine off. Idle the
vehicle with the air conditioning turned off, until the
pointer drops back into the normal range.
UNDERSTANDING YOUR INSTRUMENT PANEL 131
4

After Starting
The idle speed will automatically decrease as the engine
warms up.
CAUTION!
Long periods of engine idling, especially at high
engine speeds can cause excessive exhaust tempera-
tures which can damage your vehicle. Do not leave
your vehicle unattended with the engine running.
ENGINE BLOCK HEATER Ð IF EQUIPPED
The engine block heater warms engine coolant and
permits quicker starts in cold weather. Connect the cord
to a standard 110-115 volt AC electrical outlet with
grounded, three wire extension cord.
Use the heater when temperatures below 0ÉF (-18ÉC) are
expected to last for several days.The engine block heater cord is located:
²6-cylinder engine Ð bundled and fastened to the
injector rail between injectors 1 and 2.
²V-8 engine Ð coiled and strapped to the transmission
filler tube.
WARNING!
Remember to disconnect the cord before driving.
Damage to the 110-115 volt AC electrical cord could
cause electrocution.
178 STARTING AND OPERATING

Over Temperature Mode
The transmission electronics constantly monitor the
transmission oil temperature. If the transmission gets too
hot, the transmission will change the way it shifts to help
control the condition. This may result in a slightly
different feeling or response during normal operation in
D (Drive) position. If the transmission becomes hot
enough the O/D OFF indicator light and TRANS OVER
TEMP warning light in the instrument cluster may come
on. After the transmission cools down, it will return to
normal operation.
Torque Converter Clutch
A feature designed to improve fuel economy has been
added to the automatic transmission of this vehicle. A
clutch within the torque converter engages automatically
at calibrated speeds. This may result in a slightly differ-
ent feeling or response during normal operation in high
gear. When the vehicle speed drops or during accelera-
tion, the clutch automatically and smoothly disengages.NOTE:
²The torque converter clutch will not engage until the
transmission fluid and engine coolant are warm (usu-
ally after 1±3 miles (1.6±4.8 km) of driving). Because
engine speed is higher when the torque converter
clutch is not engaged, it may seem as if the transmis-
sion is not shifting into ªOverdriveº when cold. This is
considered a normal condition. Pressing the ªO/D
OFFº switch will show that the transmission is able to
shift into and out of ªOverdrive.º
²If the vehicle has not been driven for several days, the
first few seconds of operation after shifting the trans-
mission into gear may seem sluggish. This is due to the
transmission fluid partially draining from the torque
converter into the transmission. This is considered a
normal condition and will not cause damage to the
transmission. The torque converter will refill within 5
seconds of shifting from P (Park) into any other gear
position.
STARTING AND OPERATING 185
5

CAUTION!
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 trips 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)
²Trailer towing
²Taxi, Police, or delivery service (Commercial Service)
²Off road or desert operation
²If equipped for and operating with E-85 (ethanol) fuel
IfANYof these apply to you, then change your engine oil
every 3,000 miles (5 000 km) or 3 months, whichever
comes first, and follow the maintenance recommenda-
tions in ªMaintenance Schedule B.º
If none of these apply to you, then change your engine oil
every 6,000 miles (10 000 km) or 6 months, whichever
comes first.
NOTE:Under no circumstances should oil change in-
tervals exceed 6,000 miles (10 000 km) or 6 months
whichever comes first.
258 MAINTAINING YOUR VEHICLE

Engine Oil Selection
For best performance and maximum protection for all
engines under all types of operating conditions, the
manufacturer recommends engine oils that are API Cer-
tified and meet the requirements of DaimlerChrysler
Material Standard MS-6395.
American Petroleum Institute (API) Engine Oil
Identification Symbol
This symbol means that the oil has
been certified by the American
Petroleum Institute (API). The
manufacturer only recommends
API Certified engine oils.
Engine Oil Viscosity Chart
The proper SAE viscosity grade of engine oil should be
selected based on the following recommendation and be
within the operating temperature shown in the engine oil
viscosity chart.
4.0L Engines
MAINTAINING YOUR VEHICLE 259
7

the transmission with an improper fluid level will greatly
reduce the life of the transmission and of the fluid.
To check the automatic transmission fluid level properly,
the following procedure must be used:
1. The vehicle must be on level ground.
2. The engine should be running at curb idle speed for a
minimum of 60 seconds.
3. Fully apply parking brake.
4. Apply the brakes and shift the transmission into P
(Park).
5. The fluidMUSTbe checked with the transmission in
P (Park) to be sure that the fluid is accurate.
6. Wipe the dipstick clean and reinsert until seated.
Remove dipstick and note reading.At normal operating temperature (approximately 180É F
(82É C), the fluid level is correct if it is in the HOT region
(cross-hatched area) on the oil level indicator. The fluid
level indicator should be in the COLD region at 70É F (21É
C) fluid temperature.
If the fluid level is low, add sufficient fluid to bring to the
proper level. Refer to Recommended Fluids, Lubricants
and Genuine Parts for correct fluid type.
Fluid is added through the dipstick tube.
NOTE:To prevent dirt and water from entering the
transmission after checking or replenishing fluid, make
certain that the dipstick cap is properly reseated.
Fluid Level Check ± 4.7L Engines (5±45RFE)
Check the fluid level while the transmission is at normal
operating temperature 180ÉF (82ÉC). This occurs after at
278 MAINTAINING YOUR VEHICLE

least 15 miles (25 km) of driving. At normal operating
temperature the fluid cannot be held comfortably be-
tween the fingertips.
To check the automatic transmission fluid level properly,
the following procedure must be used:
1. Operate the engine at idle speed and normal operating
temperature.
2. The vehicle must be on level ground.
3. Fully apply the parking brake and press the brake
pedal.
4. Place the gear selector momentarily in each gear
position ending with the lever in P (Park).
5. Remove the dipstick, wipe it clean and reinsert it until
seated.
6. Remove the dipstick again and note the fluid level on
both sides. The fluid level should be between the ªHOTº(upper) reference holes on the dipstick at normal operat-
ing temperature. Verify that solid coating of oil is seen on
both sides of the dipstick. If the fluid is low, add as
required into the dipstick tube.Do not overfill.After
adding any quantity of oil through the oil fill tube, wait
a minimum of two (2) minutes for the oil to fully drain
into the transmission before rechecking the fluid level.
NOTE:If it is necessary to check the transmissionbelow
the operating temperature, the fluid level should be
between the two ªCOLDº (lower) holes on the dipstick
with the fluid at approximately 70ÉF (21ÉC) (room tem-
perature). If the fluid level is correctly established at
room temperature, it should be between the ªHOTº
(upper) reference holes when the transmission reaches
180ÉF (82ÉC). Remember it is best to check the level at the
normal operating temperature.
MAINTAINING YOUR VEHICLE 279
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