2007 GMC YUKON check engine

Engine Oil
If the ENGINE OIL LOW ADD OIL message
appears on the Driver Information Center (DIC),
it means you need to check your engine oil
level right away. For more information, see
ENGINE OIL LOW ADD OIL underDIC Warnings
and Messages on page 252.
You should check your engine oil level regularly;
this is an added reminder.
Checking Engine Oil
It is a good idea to check your engine oil every
time you get fuel. In order to get an accurate
reading, the oil must be warm and the vehicle must
be on level ground.
The engine oil dipstick handle is a yellow loop.
SeeEngine Compartment Overview on page 430
for the location of the engine oil dipstick.
1. Turn off the engine and give the oil several
minutes to drain back into the oil pan. If you
do not do this, the oil dipstick might not
show the actual level.
2. Pull out the dipstick and clean it with a paper
towel or cloth, then push it back in all the
way. Remove it again, keeping the tip down,
and check the level.
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When the system has calculated that oil life has
been diminished, it will indicate that an oil change
is necessary. A CHANGE ENGINE OIL SOON
message will come on. SeeDIC Warnings
and Messages on page 252. Change your 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, your engine oil and
lter 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 your oil
regularly and keep it at the proper level.
If the system is ever reset accidentally, you must
change your 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.How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to
change your engine oil and lter based on vehicle
use. Anytime your 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 a CHANGE ENGINE
OIL SOON message being turned on, reset the
system.
Always reset the engine oil life to 100% after
every oil change. It will not reset itself. To reset
the Engine Oil Life System, do the following:
1. Display the OIL LIFE REMAINING on the DIC.
2. Press and hold the SET/RESET button on
the DIC for more than ve seconds. The oil
life will change to 100%.
If the CHANGE ENGINE OIL SOON message
comes back on when you start your vehicle, the
Engine Oil Life System has not reset. Repeat
the procedure.
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5. Inspect or replace the engine air cleaner/lter.
6. Reinstall the cover and tighten the screws.
7. Reset the air lter restriction indicator, if
the vehicle has one, by pressing the top button
on the indicator.
{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 ames 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.
Automatic Transmission Fluid
When to Check and Change Automatic
Transmission Fluid
It is usually not necessary to check the
transmission uid level. A transmission uid leak
is the only reason for uid loss. If you suspect
a small leak, then use the following checking
procedures to check the uid level. However, if
there is a large leak, then it may be necessary to
have the vehicle towed to a dealership service
department and have it repaired before driving the
vehicle further.
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 inRecommended
Fluids and Lubricants on page 561.
Change the uid and lter at the intervals listed in
the Maintenance Schedule. SeeScheduled
Maintenance on page 551. Be sure to use the
transmission uid listed inRecommended Fluids
and Lubricants on page 561.
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How to Check Automatic
Transmission Fluid
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 parts 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.
Before checking the uid level, prepare your
vehicle as follows:
1. Start the engine and park your vehicle on a
level surface. Keep the engine running.
2. Apply the parking brake and place the shift
lever in PARK (P).
3. With your foot on the brake pedal, move the
shift lever through each gear range, pausing
for about three seconds in each range.
Then, move the shift lever back to PARK (P).4. Allow the engine to idle (500 – 800 rpm)
for at least one minute. Slowly release the
brake pedal.
5. Keep the engine running and press the
Trip/Fuel button until TRANS TEMP
(Transmission Temperature) displays on the
Driver Information Center (DIC).
6. Using the TRANS TEMP reading, determine
and perform the appropriate check procedure.
If the TRANS TEMP reading is not within
the required temperature ranges, allow
the vehicle to cool, or operate the vehicle until
the appropriate transmission uid temperature
is reached.
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Cold Check Procedure
Use this procedure only as a reference to
determine if the transmission has enough uid to
be operated safely until a hot check procedure
can be made. The hot check procedure is the most
accurate method to check the uid level. Perform
the hot check procedure at the rst opportunity.
Use this cold check procedure to check uid level
when the transmission temperature is between
80°F and 90°F (27°C and 32°C).
1. Locate the transmission dipstick at the rear of
the engine compartment, on the passenger’s
side of the vehicle.The dipstick handle has
this graphic. SeeEngine
Compartment Overview
on page 430for
more information.
2. Flip the handle up, and then pull out the
dipstick and wipe it with a clean rag or
paper towel.
3. Install the dipstick by pushing it back in all the
way, wait three seconds, and then pull it back
out again.
4. Check both sides of the dipstick, and read the
lower level. Repeat the check procedure to
verify the reading.
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5. If the uid level is below the COLD check
band, add only enough uid as necessary
to bring the level into the COLD band. It does
not take much uid, generally less than
one pint (0.5L). Do not overll.
6. Perform a hot check at the rst opportunity
after the transmission reaches a normal
operating temperature between 160°F to
200°F (71°C to 93°C).
7. If the uid level is in the acceptable range,
push the dipstick back in all the way, then
ip the handle down to lock the dipstick
in place.
Hot Check Procedure
Use this procedure to check the transmission uid
level when the transmission uid temperature is
between 160°F and 200°F (71°C and 93°C).
The hot check is the most accurate method to
check the uid level. The hot check should be
performed at the rst opportunity in order to verify
the cold check. The uid level rises as uid
temperature increases, so it is important to ensure
the transmission temperature is within range.
1. Locate the transmission dipstick at the rear of
the engine compartment, on the passenger’s
side of the vehicle.
The dipstick handle has
this graphic. SeeEngine
Compartment Overview
on page 430for
more information.
2. Flip the handle up, and then pull out the
dipstick and wipe it with a clean rag or
paper towel.
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What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL®coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:If you use an improper coolant
mixture, your engine could overheat and be
badly damaged. The repair cost would not be
covered by your warranty. Too much water
in the mixture can freeze and crack the engine,
radiator, heater core, and other parts.
If you have to add coolant more than four times a
year, have your dealer check your cooling system.
Notice:If you use extra inhibitors and/or
additives in your vehicle’s cooling system, you
could damage your vehicle. Use only the
proper mixture of the engine coolant listed in
this manual for the cooling system. See
Recommended Fluids and Lubricants on
page 561for more information.
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Checking Coolant
The coolant surge tank is located in the engine
compartment on the passenger’s side of the
vehicle. SeeEngine Compartment Overview on
page 430for more information on location.
{CAUTION:
Turning the surge tank pressure cap when
the engine and radiator are hot can allow
steam and scalding liquids to blow out
and burn you badly. Never turn the surge
tank pressure cap — even a little — when
the engine and radiator are hot.
The vehicle must be on a level surface. When
your engine is cold, the coolant level should be at
the FULL COLD mark.
Adding Coolant
If you need more coolant, add the proper
DEX-COOL®coolant mixture at the surge tank,
but only when the engine is cool.
{CAUTION:
You can be burned if you spill coolant
on hot engine parts. Coolant contains
ethylene glycol, and it will burn if the
engine parts are hot enough. Do not spill
coolant on a hot engine.
When replacing the pressure cap, make sure it is
hand-tight and fully seated.
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