2010 GMC YUKON light

What to Do with Used Oil
Used engine oil contains certain elements that can 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. Recycle it by taking it to a
place that collects used oil.
Engine Air Cleaner/Filter
SeeEngine Compartment Overviewon page 6‑16for
the location of the engine air cleaner/filter.
Inspect the air cleaner/filter at the Maintenance II
intervals and replace it at the first oil change after
each 50,000 mile (80 000 km) interval. See Scheduled
Maintenance
on page 7‑3for more information.
If driving on dusty/dirty conditions, inspect the filter
at each engine oil change.
How to Inspect the Engine
Air Cleaner/Filter
To inspect the air cleaner/filter, remove the engine
air cleaner/filter from the vehicle by following Steps 1
through 6. When the engine air cleaner/filter is
removed, lightly shake it to release loose dust and dirt.
If the engine air cleaner/filter remains caked with dirt,
a new filter is required.
Replacing the Engine Air Cleaner/Filter
1. Locate the air cleaner/ filter assembly.
See Engine
Compartment Overview
on page 6‑16.
2. Loosen the four screws on the cover of the housing and lift up the cover.
6-22

Brakes
Brake Fluid
The brake master cylinder
reservoir is filled with
DOT 3 brake fluid. See
Engine Compartment
Overview
on page 6‑16for the location of the
reservoir.
There are only two reasons why the brake fluid level in
the reservoir might go down:
.The brake fluid level goes down because of normal
brake lining wear. When new linings are installed,
the fluid level goes back up.
.A fluid leak in the brake hydraulic system can also
cause a low fluid level. Have the brake hydraulic
system fixed, since a leak means that sooner or
later the brakes will not work well. Do not top off the brake fluid. Adding fluid does not
correct a leak. If fluid is added when the linings are
worn, there will be too much fluid when new brake
linings are installed. Add or remove brake fluid, as
necessary, only when work is done on the brake
hydraulic system.
{WARNING:
If too much brake fluid is added, it can spill on
the engine and burn, if the engine is hot enough.
You or others could be burned, and the vehicle
could be damaged. Add brake fluid only when
work is done on the brake hydraulic system.
See
“Checking Brake Fluid” in this section.
When the brake fluid falls to a low level, the brake
warning light comes on. See Brake System Warning
Light on page 4‑36.
Refer to the Maintenance Schedule to determine when
to check the brake fluid. See Scheduled Maintenance
on page 7‑3.
6-42

Brake Wear
This vehicle has disc brakes. Disc brake pads have
built-in wear indicators that make a high-pitched
warning sound when the brake pads are worn and new
pads are needed. The sound can come and go or be
heard all the time the vehicle is moving, except when
applying the brake pedal firmly.
{WARNING:
The brake wear warning sound means that soon
the brakes will not work well. That could lead to
an accident. When the brake wear warning sound
is heard, have the vehicle serviced.
Notice: Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates can cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
the brakes. Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts
in the proper sequence to torque specifications in
Capacities and Specifications on page 6‑126.
Brake linings should always be replaced as complete
axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in pedal
travel. This could be a sign that brake service might
be required.
Brake Adjustment
Every brake stop, the disc brakes adjust for wear.
6-44

Notice:If you leave the radio or other accessories
on during the jump starting procedure, they could
be damaged. The repairs would not be covered by
the warranty. Always turn off the radio and other
accessories when jump starting the vehicle.
3. Turn off the ignition on both vehicles. Unplug unnecessary accessories plugged into the
cigarette lighter or the accessory power outlets.
Turn off the radio and all the lamps that are not
needed. This avoids sparks and helps save both
batteries. And it could save the radio!
4. Open the hood on the other vehicle and locate the positive (+) and negative (−) terminal locations on
that vehicle.
Your vehicle has a remote positive (+) jump starting
terminal and a remote negative (−) jump starting
terminal. You should always use these remote
terminals instead of the terminals on the battery.
If the vehicle has a remote positive (+) terminal, it
is located under a red plastic cover at the positive
battery post. To uncover the remote positive (+)
terminal, open the red plastic cover.
The remote negative (−) terminal is a stud located
on the right front of the engine, where the negative
battery cable attaches.
See Engine Compartment Overview
on page 6‑16for more information on the location of the remote
positive (+) and remote negative (−) terminals.
6-47

{WARNING:
An electric fan can start up even when the engine
is not running and can injure you. Keep hands,
clothing and tools away from any underhood
electric fan.
{WARNING:
Using an open flame near a battery can cause
battery gas to explode. People have been hurt
doing this, and some have been blinded. Use a
flashlight if you need more light.(Continued)
WARNING: (Continued)
Be sure the battery has enough water. You do not
need to add water to the battery installed in your
new vehicle. But if a battery has filler caps, be
sure the right amount of fluid is there. If it is low,
add water to take care of that first. If you do not,
explosive gas could be present.
Battery fluid contains acid that can burn you.
Do not get it on you. If you accidentally get it in
your eyes or on your skin, flush the place with
water and get medical help immediately.
{WARNING:
Fans or other moving engine parts can injure you
badly. Keep your hands away from moving parts
once the engine is running.
6-48

What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeeRecommended Fluids and
Lubricants on page 7‑11.
Headlamp Aiming
The vehicle has a visual optical headlamp aiming
system. The aim of the headlamps have been preset at
the factory and should need no further adjustment.
However, if the vehicle is damaged in a crash, the aim
of the headlamps may be affected and adjustment may
be necessary.
If oncoming vehicles flash their high beams at you, this
may mean the vertical aim of your headlamps needs to
be adjusted.
It is recommended that the vehicle is taken to your
dealer for service if the headlamps need to be adjusted.
It is possible however, to re-aim the headlamps as
described. The vehicle should:
.Be placed so the headlamps are 25 ft. (7.6 m) from
a light colored wall.
.Have all four tires on a level surface which is level
all the way to the wall.
.Be placed so it is perpendicular to the wall.
.Not have any snow, ice, or mud on it.
.Be fully assembled and all other work stopped
while headlamp aiming is being performed.
.Normally loaded with a full tank of fuel and one
person or 160 lbs (75 kg) sitting on the driver seat.
.Have the tires properly inflated.
.Have the spare tire is in its proper location in the
vehicle.
Headlamp aiming is done with the vehicle's low-beam
headlamps. The high-beam headlamps will be correctly
aimed if the low-beam headlamps are aimed properly.
6-55

To adjust the vertical aim:1. Open the hood. See Hood Release on page 6‑14
2. Locate the aim dot on the lens of the low‐beam
headlamp.
3. Record the distance from the ground to the aim dot on the low‐beam headlamp.
4. At a wall, measure from the ground upward (A) tothe 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 flat surface.
6-56

7. Locate the vertical headlamp aiming screws, whichare under the hood near each headlamp assembly.
The adjustment screw can be turned with an
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.
9. Make sure that the light from the headlamp is
positioned at the bottom edge of the horizontal
tape line. The lamp on the left (A) shows the
correct headlamp aim. The lamp on the right (B)
shows the incorrect headlamp aim.
10. Repeat Steps 7 through 9 for the opposite headlamp.
6-57