lock GMC YUKON 2008 Owner's Manual

Consistency of Readings
Always check the uid level at least twice using the
procedure described previously. Consistency (repeatable
readings) is important to maintaining proper uid
level. If readings are still inconsistent, contact your
dealer/retailer.
How to Add Automatic
Transmission Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission uid to use. SeeRecommended
Fluids and Lubricants on page 6-13.
Using a funnel, add uid down the transmission dipstick
tube only after checking the transmission uid while it
is hot. A cold check is used only as a reference. If
the uid level is low, add only enough of the proper uid
to bring the level up to the HOT area for a hot check.
It does not take much uid, generally less than one pint
(0.5 L). Do not overll.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 6-13.
After adding uid, recheck the uid level as
described under “How to Check Automatic
Transmission Fluid,” earlier in this section.
When the correct uid level is obtained, push the
dipstick back in all the way; then ip the handle
down to lock the dipstick in place.
Automatic Transmission Fluid
(6-Speed Transmission)
When to Check and Change Automatic
Transmission Fluid
It is usually not necessary to check the transmission
uid level. The only reason for uid loss is a
transmission leak or overheating the transmission. 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 dealer/retailer service department
and have it repaired before driving the vehicle further.
5-24

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 side of the
vehicle.
The dipstick handle has
this graphic. SeeEngine
Compartment Overview on
page 5-14for 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.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.
5-26

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 side of the
vehicle.
The dipstick handle has
this graphic. SeeEngine
Compartment Overview on
page 5-14for 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.
5. Safe operating level is within the HOT cross hatch
band on the dipstick. If the uid level is not within
the HOT band, and the transmission temperature is
between 160°F and 200°F (71°C and 93°C), add
or drain uid as necessary to bring the level into the
HOT band. If the uid level is low, add only
enough uid to bring the level into the HOT band. It
does not take much uid, generally less than one
pint (0.5L). Do not overll.
6. 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.
5-27

{CAUTION:
Adding only plain water to the cooling system
can be dangerous. Plain water, or some other
liquid such as alcohol, can boil before the
proper coolant mixture will. The vehicle’s
coolant warning system is set for the proper
coolant mixture. With plain water or the wrong
mixture, the engine could get too hot but you
would not get the overheat warning. The
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:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{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.
1. You can remove the
coolant surge tank
pressure cap when the
cooling system,
including the coolant
surge tank pressure
cap and upper radiator
hose, is no longer hot.
Turn the pressure cap slowly counterclockwise
about one full turn. If you hear a hiss, wait for that to
stop. A hiss means there is still some pressure left.
2. Then keep turning the pressure cap slowly, and
remove it.
5-37

4. At a wall, measure from the ground upward (A) to
the recorded distance from Step 3 and mark it.
5. Draw or tape a horizontal line (B) on the wall the
width of the vehicle at the height of the mark in
Step 4.
Notice:Do not cover a headlamp to improve beam
cut-off when aiming. Covering a headlamp may
cause excessive heat build-up which may cause
damage to the headlamp.
6. Turn on the low-beam headlamps and place a
piece of cardboard or equivalent in front of the
headlamp not being adjusted. This allows only the
beam of light from the headlamp being adjusted
to be seen on the at surface.7. Locate the vertical headlamp aiming screws, which
are under the hood near each headlamp assembly.
The adjustment screw can be turned with a E8
Torx
®socket.
8. Turn the vertical aiming screw until the headlamp
beam is aimed to the horizontal tape line. Turn it
clockwise or counterclockwise to raise or lower the
angle of the beam.
5-58

Taillamps, Turn Signal, Stoplamps
and Back-up Lamps
A. Taillamp/
Turn Signal Lamp
B. Back-up Lamp
C. Stoplamp/Taillamp
If your vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
To replace one of these bulbs:
1. Open the liftgate. SeePower Liftgate on page 2-15
for more information.2. Remove the two
screws from the
taillamp assembly.
3. Pull the taillamp assembly rearward until you
disengage the inner pins on the taillamp assembly
from the vehicle.
4. Press the release tab, if bulb socket has one, and
turn the bulb socket counterclockwise to remove it
from the taillamp assembly.
5. Pull the old bulb straight out from the bulb socket.
6. Press a new bulb into the bulb socket and insert
it into the taillamp assembly. Turn the bulb socket
clockwise into the taillamp assembly until it clicks.
7. Reinstall the taillamp assembly. When reinstalling,
make sure to line up the pins on the taillamp
assembly with the vehicle. If you do not do this, you
will not be able correctly install the taillamp
assembly.
5-60

License Plate Lamp
1. Remove the two screws holding each of the license
plate lamps to the molding that is part of the
liftgate.
2. Twist and pull the license plate lamp forward
through the molding opening.3. Turn the bulb socket counterclockwise and pull the
bulb straight out of the socket.
4. Install the new bulb.
5. Reverse Steps 1 through 3 to reinstall the license
plate lamp.
Replacement Bulbs
Exterior Lamp Bulb Number
Back-up Lamp 7441
License Plate Lamp 168
Rear Turn Signal Lamp, Taillamp,
and Stoplamp3057KX
For replacement bulbs not listed here, contact your
dealer/retailer.
If your vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
5-61

Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for wear
or cracking. SeeScheduled Maintenance on page 6-4.
Replacement blades come in different types and
are removed in different ways. To replace the wiper
blade assembly:
1. Pull the windshield wiper arm connector away from
the windshield.
2. Squeeze the grooved areas on each side of the
blade, and turn the blade assembly away from
the arm connector.3. Install the new blade onto the arm connector and
make sure the grooved areas are fully set in the
locked position.
For the proper type and size, seeMaintenance
Replacement Parts on page 6-15.
5-62

Backglass Wiper Blade Replacement
1. Lift the wiper blade assembly up and out of the park
rest position.
2. Pull the wiper blade assembly away from the
backglass. The backglass wiper blade will not
lock in a vertical position, so care should be used
when pulling it away from the vehicle.3. Turn the wiper blade assembly, and pull it off of the
wiper arm. Hold the wiper arm in position and push
the blade away from the wiper arm.
4. Replace the wiper blade.
5. Return the wiper blade assembly to the park rest
position.
5-63

TPMS Sensor Matching Process
Each TPMS sensor has a unique identication code.
Any time you rotate your vehicle’s tires or replace one or
more of the TPMS sensors, the identication codes
will need to be matched to the new tire/wheel position.
The sensors are matched to the tire/wheel positions
in the following order: driver side front tire, passenger
side front tire, passenger side rear tire, and driver
side rear tire using a TPMS diagnostic tool. See your
dealer/retailer for service.
The TPMS sensors can also be matched to each
tire/wheel position by increasing or decreasing the tire’s
air pressure. If increasing the tire’s air pressure, do
not exceed the maximum ination pressure indicated on
the tire’s sidewall.
To decrease air-pressure out of a tire you can use the
pointed end of the valve cap, a pencil-style air pressure
gage, or a key.
You have two minutes to match the rst tire/wheel
position, and ve minutes overall to match all four
tire/wheel positions. If it takes longer than two minutes,
to match the rst tire and wheel, or more than ve
minutes to match all four tire and wheel positions the
matching process stops and you need to start over.The TPMS sensor matching process is outlined below:
1. Set the parking brake.
2. Turn the ignition switch to ON/RUN with the
engine off.
3. Press the Remote Keyless Entry (RKE) transmitter’s
LOCK and UNLOCK buttons at the same time for
approximately ve seconds. The horn sounds twice
to signal the receiver is in relearn mode and
TIRE LEARNING ACTIVE message displays on the
DIC screen.
4. Start with the driver side front tire.
5. Remove the valve cap from the valve cap stem.
Activate the TPMS sensor by increasing or
decreasing the tire’s air pressure for ve seconds,
or until a horn chirp sounds. The horn chirp,
which may take up to 30 seconds to sound,
conrms that the sensor identication code has
been matched to this tire and wheel position.
6. Proceed to the passenger side front tire, and repeat
the procedure in Step 5.
7. Proceed to the passenger side rear tire, and repeat
the procedure in Step 5.
5-77