2009 GMC YUKON engine

Checking Brake Fluid
Check brake uid by looking at the brake uid reservoir.
SeeEngine Compartment Overview on page 5-14.
The uid level should be
above MIN. If it is not,
have the brake hydraulic
system checked to
see if there is a leak.
After work is done on the brake hydraulic system,
make sure the level is above the MIN but not over the
MAX mark.
What to Add
Use only new DOT-3 brake uid from a sealed container.
SeeRecommended Fluids and Lubricants on page 6-13.
Always clean the brake uid reservoir cap and the area
around the cap before removing it. This helps keep
dirt from entering the reservoir.
{CAUTION:
With the wrong kind of uid in the brake hydraulic
system, the brakes might not work well. This could
cause a crash. Always use the proper brake uid.
Notice:
Using the wrong uid can badly damage brake
hydraulic system parts. For example, just a
few drops of mineral-based oil, such as engine
oil, in the brake hydraulic system can damage
brake hydraulic system parts so badly that they
will have to be replaced. Do not let someone
put in the wrong kind of uid.
If brake uid is spilled on the vehicle’s painted
surfaces, the paint nish can be damaged. Be
careful not to spill brake uid on the vehicle.
If you do, wash it off immediately. SeeWashing
Your Vehicle on page 5-111.
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Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. The vehicle
was designed and tested with top-quality brake parts.
When parts of the braking system are replaced — for
example, when the brake linings wear down and new
ones are installed — be sure to get new approved
replacement parts. If this is not done, the brakes might
not work properly. For example, if someone puts in
brake linings that are wrong for the vehicle, the balance
between the front and rear brakes can change — for the
worse. The braking performance expected can change in
many other ways if the wrong replacement brake parts
are installed.
Battery
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
This vehicle has a maintenance free battery. When it is
time for a new battery, see your dealer/retailer for
one that has the replacement number shown on the
original battery’s label. SeeEngine Compartment
Overview on page 5-14for battery location.Warning:Battery posts, terminals, and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.
Vehicle Storage
{CAUTION:
Batteries have acid that can burn you and gas that
can explode. You can be badly hurt if you are not
careful. SeeJump Starting on page 5-45for tips
on working around a battery without getting hurt.
Infrequent Usage: If the vehicle is driven infrequently,
remove the black, negative (−) cable from the battery.
This helps keep the battery from running down.
Extended Storage: For extended storage of the vehicle,
remove the black, negative (−) cable from the battery or
use a battery trickle charger. This helps maintain the
charge of the battery over an extended period of time.
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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.
SeeEngine Compartment Overview on page 5-14
for more information on the location of the remote
positive (+) and remote negative (−) terminals.
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{CAUTION:
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.
{CAUTION:
Using a match near a battery can cause battery
gas to explode. People have been hurt doing this,
and some have been blinded. Use a ashlight if
you need more light.
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 ller caps, be
CAUTION: (Continued)
CAUTION: (Continued)
sure the right amount of uid is there. If it is low,
add water to take care of that rst. If you do not,
explosive gas could be present.
Battery uid contains acid that can burn you.
Do not get it on you. If you accidentally get it in
your eyes or on your skin, ush the place with
water and get medical help immediately.
{CAUTION:
Fans or other moving engine parts can injure you
badly. Keep your hands away from moving parts
once the engine is running.
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5. Check that the jumper cables do not have loose or
missing insulation. If they do, you could get a
shock. The vehicles could be damaged too.
Before you connect the cables, here are some
basic things you should know. Positive (+) will go to
positive (+) or to a remote positive (+) terminal if
the vehicle has one. Negative (−) will go to a heavy,
unpainted metal engine part or to a remote
negative (−) terminal if the vehicle has one.
Do not connect positive (+) to negative (−)oryou
will get a short that would damage the battery
and maybe other parts too. And do not connect the
negative (−) cable to the negative (−) terminal on
the dead battery because this can cause sparks.
6. Connect the red
positive (+) cable to the
positive (+) terminal
of the vehicle with the
dead battery. Use
a remote positive (+)
terminal if the
vehicle has one.7. Do not let the other end touch metal. Connect it to
the positive (+) terminal of the good battery. Use a
remote positive (+) terminal if the vehicle has one.
8. Now connect the black negative (−) cable to the
negative (−) terminal of the good battery. Use a
remote negative (−) terminal if the vehicle has one.
Do not let the other end touch anything until the next
step. The other end of the negative (−) cable does
not go to the dead battery. It goes to a heavy,
unpainted metal engine part or to the remote
negative (−) terminal on the vehicle with the dead
battery.
9. Connect the other end of the negative (−) cable to
the remote negative (−) terminal, on the vehicle with
the dead battery.
10. Now start the vehicle with the good battery and run
the engine for a while.
11. Try to start the vehicle that had the dead battery.
If it will not start after a few tries, it probably needs
service.
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Notice:If the jumper cables are connected or
removed in the wrong order, electrical shorting may
occur and damage the vehicle. The repairs would
not be covered by your warranty. Always connect
and remove the jumper cables in the correct
order, making sure that the cables do not touch
each other or other metal.
A. Heavy, Unpainted Metal Engine Part or Remote
Negative (−) Terminal
B. Good Battery or Remote Positive (+) and Remote
Negative (−) Terminals
C. Dead Battery or Remote Positive (+) TerminalTo disconnect the jumper cables from both vehicles do
the following:
1. Disconnect the black negative (−) cable from the
vehicle that had the bad battery.
2. Disconnect the black negative (−) cable from the
vehicle with the good battery.
3. Disconnect the red positive (+) cable from the
vehicle with the good battery.
4. Disconnect the red positive (+) cable from the other
vehicle.
5. Return the remote positive (+) terminal cover, if the
vehicle has one, to its original position.
Jumper Cable Removal
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(E) Tire Identication Number (TIN):The letters
and numbers following DOT code are the Tire
Identication Number (TIN). The TIN shows the
manufacturer and plant code, tire size, and date the
tire was manufactured. The TIN is molded onto both
sides of the tire, although only one side may have
the date of manufacture.
(F) Tire Ply Material
:The type of cord and
number of plies in the sidewall and under the
tread.
(G) Single Tire Maximum Load
:Maximum load
that can be carried and the maximum pressure
needed to support that load when used as a
single. For information on recommended
tire pressure seeInflation - Tire Pressure on
page 5-70andLoading the Vehicle on page 4-33.
Tire Size
The following examples show the different parts of
a tire size.
(A) Passenger (P-Metric) Tire
:The United States
version of a metric tire sizing system. The letter P
as the rst character in the tire size means a
passenger vehicle tire engineered to standards
set by the U.S. Tire and Rim Association.
Passenger (P-Metric) Tire
Light Truck (LT-Metric) Tire
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(A) Light Truck (LT-Metric) Tire:The United
States version of a metric tire sizing system.
The letters LT as the rst two characters in the
tire size means a light truck tire engineered to
standards set by the U.S. Tire and Rim Association.
(B) Tire Width
:The three-digit number indicates
the tire section width in millimeters from sidewall to
sidewall.
(C) Aspect Ratio
:A two-digit number that
indicates the tire height-to-width measurements.
For example, if the tire size aspect ratio is 75, as
shown in item C of the light truck (LT-Metric) tire
illustration, it would mean that the tire’s sidewall is
75 percent as high as it is wide.
(D) Construction Code
:A letter code is used to
indicate the type of ply construction in the tire. The
letter R means radial ply construction; the letter D
means diagonal or bias ply construction; and the
letter B means belted-bias ply construction.(E) Rim Diameter
:Diameter of the wheel in
inches.
(F) Service Description
:The service description
indicates the load range and speed rating of a
tire. The load index represents the load carry
capacity a tire is certied to carry. The load index
can range from 1 to 279. The speed rating is
the maximum speed a tire is certied to carry a
load. Speed ratings range from A to Z.
Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
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