2005 PONTIAC GTO engine

What Kind of Engine Oil to Use
Look for two things:
•GM4718M
Your vehicle’s engine requires a special oil meeting
GM Standard GM4718M. Oils meeting this
standard may be identified as synthetic. However,
not allsyntheticoils will meet this GM standard.
You should look for and use only an oil that meets
GM Standard GM4718M.Notice:If you use oils that do not have the
GM4718M Standard designation, you can cause
engine damage not covered by your warranty.
•SAE 5W-30
As shown in the viscosity chart, SAE 5W-30 is best
for your vehicle.
These numbers on an oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 20W-50.
Oils meeting these
requirements should also
have the starburst
symbol on the container.
This symbol indicates
that the oil has been
certified by the American
Petroleum Institute (API).
You should look for this on the oil container, and
useonlythose oils that are identified as meeting
GM Standard GM4718M and have the starburst symbol
on the front of the oil container.
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Your vehicle’s engine is filled at the factory with a
Mobil 1®synthetic oil, which meets all requirements
for your vehicle.
Substitute Engine Oil: When adding oil to maintain
engine oil level, oil meeting GM Standard GM4718M
may not be available. You can add substitute oil
designated SAE 5W-30 with the starburst symbol at all
temperatures. Substitute oil not meeting GM Standard
GM4718M should not be used for an oil change.
Engine Oil Additives
Do not add anything to the oil. The recommended oils
with the starburst symbol that meet GM Standard
GM4718M are all you will need for good performance
and engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you know
when to change the engine oil and filter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated can
vary considerably. For the oil life system to work
properly, you must reset the system every time the oil is
changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A Service Engine Oil light on the trip
computer display will come on. SeeTrip Computer on
page 3-33. Change engine oil as soon as possible within
the next 600 miles (1 000 km). It is possible that, if
you are driving under the best conditions, the oil
life system may not indicate that an oil change is
necessary for over a year. However, the engine oil and
filter must be changed at least once a year and at
this time the system must be reset. Your dealer has
GM-trained service people who will perform this
work using genuine GM parts and reset the system. It is
also important to check engine oil regularly and keep
it at the proper level.
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If the system is ever reset accidentally, you must
change the oil at 3,000 miles (5 000 km) since your last
oil change. Remember to reset the oil life system
whenever the oil is changed.
After changing the engine oil, reset the system by
performing the following steps:
How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to change
the engine oil and filter based on vehicle use. Anytime
engine oil is changed, reset the system so it can
calculate when the next oil change is required. If a
situation occurs where you change your oil prior to
the Service Engine Oil light being turned on, reset
the system.
1. With the engine off, turn the ignition key to ON.
2. Fully press and release the accelerator pedal slowly
two times within five seconds.
3. Turn the key to LOCK.
If the Service Engine Oil light comes back on when
you start your vehicle, the engine oil life system
has not reset. Repeat the procedure.
What to Do with Used Oil
Used engine oil contains certain elements that may be
unhealthy for your skin and could even cause cancer.
Do not let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good
hand cleaner. Wash or properly dispose of clothing or
rags containing used engine oil. See the manufacturer’s
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from the
filter before disposal. Never dispose of oil by putting it
in the trash, pouring it on the ground, into sewers, or into
streams or bodies of water. Instead, recycle it by
taking it to a place that collects used oil. If you have a
problem properly disposing of used oil, ask your
dealer, a service station, or a local recycling center
for help.
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Engine Air Cleaner/Filter
SeeEngine Compartment Overview on page 5-12for
more information on the location of the engine air
cleaner/filter.
When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/filter at every oil change and
replace at the first oil change after 25,000 miles
(41 500 km). SeeScheduled Maintenance on page 6-4
for more information.
How to Inspect the Engine Air
Cleaner/Filter
To inspect the air cleaner/filter, remove the filter from
the vehicle and lightly shake the filter to release
loose dust and dirt. If the filter remains caked with dirt, a
new filter is required.
To inspect or replace the engine air cleaner/filter, do the
following:
1. Remove the screws that hold the cover on.
2. Lift off the cover.
3. Inspect or replace the engine air cleaner/filter.
4. Put the cover back on tightly.
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{CAUTION:
Operating the engine with the air cleaner/lter
off can cause you or others to be burned. The
air cleaner not only cleans the air; it helps to
stop ame if the engine backres. If it is not
there and the engine backres, you could
be burned. Do not drive with it off, and be
careful working on the engine with the air
cleaner/lter off.
Notice:If the air cleaner/lter is off, a backre can
cause a damaging engine re. And, dirt can
easily get into your engine, which will damage it.
Always have the air cleaner/lter in place when you
are driving.
Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change the fluid and filter at the intervals listed in
Additional Required Services on page 6-6, and be sure
to use the transmission fluid listed inRecommended
Fluids and Lubricants on page 6-12.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little uid can damage
your transmission. Too much can mean that some
of the uid could come out and fall on hot engine
part or exhaust system parts, starting a re.
Too little uid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission uid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving in the
following conditions:
•When outside temperatures are above 90°F (32°C).
•At high speed for quite a while.
•In heavy traffic — especially in hot weather.
To get the right reading, the fluid should be at
normal operating temperature, which is 180°F to
200°F (82°C to 93°C).
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Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C). If it is colder than 50°F (10°C), drive the vehicle
in DRIVE (D) until the engine temperature gage
moves and then remains steady for 10 minutes.
A cold fluid check can be made after the vehicle has
been sitting for eight hours or more with the engine off,
but this is used only as a reference. Let the engine
run at idle for five minutes if outside temperatures are
50°F (10°C) or more. If it is colder than 50°F (10°C), you
may have to idle the engine longer. Should the fluid
level be low during this cold check, you must check the
fluid hot before adding fluid. Checking the fluid hot
will give you a more accurate reading of the fluid level.
Checking the Fluid Level
Prepare your vehicle as follows:
•Park your vehicle on a level place. Keep the
engine running.
•With the parking brake applied, place the shift lever
in PARK (P).
•With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever in PARK (P).
•Let the engine run at idle for three minutes or more.Then, without shutting off the engine, follow
these steps:
The automatic transmission dipstick is located at the
rear of the engine compartment, on the passenger’s side
of the vehicle. SeeEngine Compartment Overview on
page 5-12for more information on location.
1. Unclip the handle and remove the dipstick; wipe it
clean with a clean rag or paper towel and re-insert
it fully. Remove it again and read the fluid level.
2. Check both sides of the dipstick, and read the lower
level. The fluid level must be in the COLD area for
a cold check or in the cross-hatched HOT area
for a hot check.
3. If the fluid level is in the acceptable range, push the
dipstick back in all the way.
Remember to always replace the dipstick and lock
the handle down.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission fluid to use. SeeRecommended
Fluids and Lubricants on page 6-12.
Add fluid only after checking the transmission fluid while
it is hot. A cold check is used only as a reference. If
the fluid level is low, add only enough of the proper fluid
to bring the level up to the HOT area for a hot check.
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The level should never read over the HOT mark, so be
careful not to add too much. It does not take much
fluid, generally less than 0.6 pints (0.3 L). Do not overfill.
Notice:Use of the incorrect automatic transmission
uid may damage your vehicle, and the damages
may not be covered by your warranty. Always
use the automatic transmission uid listed in
Recommended Fluids and Lubricants on page 6-12.
•After adding fluid, recheck the fluid level as
described under “How to Check,” earlier in
this section.
•When the correct fluid level is obtained, push the
dipstick back in all the way.
Remember to always replace the dipstick and lock
the handle down.
•If fluid has to be added often, there may be a
problem or leak and you should see your dealer.
Manual Transmission Fluid
When to Check
A good time to have your manual transmission fluid
checked is when the engine oil is changed. However,
the fluid in your manual transmission does not
require changing.
How to Check
Because this operation can be difficult, you may choose
to have this done at your dealership service department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading.
Notice:Too much or too little uid can damage
your transmission. Too much can mean that some
of the uid could come out and fall on hot engine
part or exhaust system parts, starting a re.
Too little uid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission uid.
Check the fluid level only when your engine is off, the
vehicle is parked on a level place and the transmission
is cool enough for you to rest your fingers on the
transmission case.
Then, follow these steps:
1. Remove the reverse light switch.
2. Check that the lubricant level is up to the bottom of
the switch hole.
3. If the fluid level is good, install the switch and be
sure it is fully seated. If the fluid level is low, add
more fluid as described in the next steps.
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How to Check and Add Fluid
To check the fluid level, look at the markings on the
reservoir. If the fluid level is between the MIN and the
MAX line, the fluid level is correct. If the fluid level
is between these marks do not remove the cap, as the
fluid will quickly absorb moisture. SeeEngine
Compartment Overview on page 5-12for more
information on reservoir location.
If fluid does need to be added, first turn the vehicle off.
Remove the cap and add the proper fluid. Remember
to replace the cap and clean up any spilled fluid.
Engine Coolant
The cooling system in your vehicle is filled with
DEX-COOL®engine coolant. This coolant is designed
to remain in the vehicle for five years or 150,000 miles
(240 000 km), whichever occurs first, if only
DEX-COOL
®extended life coolant is added.The following explains the cooling system and how to
add coolant when it is low. If there is a problem
with engine overheating or if coolant needs to be added
to the radiator, seeEngine Overheating on page 5-26.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
•Give freezing protection down to−34°F (−37°C).
•Give boiling protection up to 265°F (129°C).
•Protect against rust and corrosion.
•Help keep the proper engine temperature.
•Let the warning lights and gages work as
they should.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
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