2001 GMC YUKON Engine parts

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Table of Contents (cont'd)
Maintenance Schedule Service and Appearance Care
Section
7
Section
6
Scheduled Maintenance
Owner Checks and Services
Periodic Maintenance InspectionsRecommended Fluids and Lubricants
Maintenance Records Fuel
Checking Fluids and Lubricants
GM Oil Life System™
Engine Air Cleaner/Filter
Passenger Compartment Air Filter (If Equipped)
Brakes
Bulb ReplacementWindshield Wiper Blade Replacement
Tires and Wheels
Appearance Care
Electrical System/Fuses and Circuit Breakers
Capacities and Specifications
Normal Maintenance Replacement Parts

1-35
CAUTION:
When an air bag inflates, there is dust in the air.
This dust could cause breathing problems for
people with a history of asthma or other
breathing trouble. To avoid this, everyone in the
vehicle should get out as soon as it is safe to do so.
If you have breathing problems but can't get out
of the vehicle after an air bag inflates, then get
fresh air by opening a window or a door.
In many crashes severe enough to inflate an air bag,
windshields are broken by vehicle deformation.
Additional windshield breakage may also occur
from the right front passenger air bag.

Air bags are designed to inflate only once. After an
air bag inflates, you'll need some new parts for your
air bag system. If you don't get them, the air bag
system won't be there to help protect you in another
crash. A new system will include air bag modules
and possibly other parts. The service manual for
your vehicle covers the need to replace other parts.
Your vehicle is equipped with a crash sensing and
diagnostic module, which records information about
the frontal air bag system. The module records
information about the readiness of the system, when
the system commands air bag inflation and driver's
safety belt usage at deployment. The module also
records speed, engine rpm, brake and throttle data.

Let only qualified technicians work on your air
bag systems. Improper service can mean that an
air bag system won't work properly. See your dealer
for service.
NOTICE:
If you damage the covering for the driver's or the
right front passenger's air bag, or the air bag
covering on the driver's and right front
passenger's seatback, the bag may not work
properly. You may have to replace the air bag
module in the steering wheel, both the air bag
module and the instrument panel for the right
front passenger's air bag, or both the air bag
module and seatback for the driver's and right
front passenger's side impact air bag. Do not
open or break the air bag coverings.

2-18
NOTICE:
Holding your key in START for longer than
15 seconds at a time will cause your battery to be
drained much sooner. And the excessive heat
can damage your starter motor. Wait about
15 seconds between each try to help avoid
draining your battery or damaging your starter.
2. If it doesn't start within 10 seconds, push the
accelerator pedal all the way to the floor, while you
hold the ignition key in START. When the engine
starts, let go of the key and let up on the accelerator
pedal. Wait about 15 seconds between each try.
When starting your engine in very cold weather
(below 0
F or
-18
C), do this:
1. With your foot off the accelerator pedal, turn the
ignition key to START and hold it there. When the
engine starts, let go of the key. Use the accelerator
pedal to maintain engine speed, if you have to, until
your engine has run for a while.2. If your engine still won't start (or starts but then
stops), it could be flooded with too much gasoline.
Try pushing your accelerator pedal all the way to
the floor and holding it there as you hold the key in
START for about three seconds. When the engine
starts, let go of the key and accelerator. If the vehicle
starts briefly but then stops again, do the same
thing, but this time keep the pedal down for five or
six seconds. This clears the extra gasoline from
the engine.
NOTICE:
Your engine is designed to work with the
electronics in your vehicle. If you add electrical
parts or accessories, you could change the way
the engine operates. Before adding electrical
equipment, check with your dealer. If you don't,
your engine might not perform properly.

2-19
Engine Coolant Heater (If Equipped)
In very cold weather, 0
F
(
-18
C) or colder, the
engine coolant heater can
help. You'll get easier
starting and better fuel
economy during engine
warm
-up. Usually, the
coolant heater should be
plugged in a minimum of
four hours prior to starting
your vehicle.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord. The
cord is located on the driver's side of the engine
compartment, near the power steering fluid reservoir.
3. Plug it into a normal, grounded 110
-volt AC outlet.
CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the wrong
kind of extension cord could overheat and cause
a fire. You could be seriously injured. Plug the
cord into a properly grounded three
-prong
11 0
-volt AC outlet. If the cord won't reach,
use a heavy
-duty three-prong extension cord
rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and store
the cord as it was before to keep it away from moving
engine parts. If you don't, it could be damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact
your dealer in the area where you'll be parking your
vehicle. The dealer can give you the best advice for that
particular area.

2-29
To release the parking brake, hold the regular brake
pedal down. Pull the bottom edge of the lever, located
above the parking brake pedal, marked BRAKE
RELEASE, to release the parking brake.
If the ignition is on when the parking brake is released,
the brake system warning light will go off.
NOTICE:
Driving with the parking brake on can cause
your rear brakes to overheat. You may have to
replace them, and you could also damage other
parts of your vehicle.
If you are towing a trailer and are parking on any hill,
see ªTowing a Trailerº in the Index. That section shows
what to do first to keep the trailer from moving.
Shifting Into PARK (P)
CAUTION:
It can be dangerous to get out of your vehicle if
the shift lever is not fully in PARK (P) with the
parking brake firmly set. Your vehicle can roll.
If you have left the engine running, the vehicle
can move suddenly. You or others could be
injured. To be sure your vehicle won't move, even
when you're on fairly level ground, use the steps
that follow. With four
-wheel drive if your
transfer case is in NEUTRAL, your vehicle will
be free to roll, even if your shift lever is in
PARK (P). So, be sure the transfer case is in a
drive gear
-- not in NEUTRAL. If you're pulling
a trailer, see ªTowing a Trailerº in the Index.

4-39
If you drive regularly in steep country, or if you're
planning to visit there, here are some tips that can make
your trips safer and more enjoyable. See ªOff
-Road
Drivingº in the Index for information about
driving off
-road.

Keep your vehicle in good shape. Check all fluid
levels and also the brakes, tires, cooling system
and transmission. These parts can work hard on
mountain roads.

Know how to go down hills. The most important
thing to know is this: let your engine do some of
the slowing down. Shift to a lower gear when you
go down a steep or long hill.
CAUTION:
If you don't shift down, your brakes could get
so hot that they wouldn't work well. You would
then have poor braking or even none going
down a hill. You could crash. Shift down to
let your engine assist your brakes on a steep
downhill slope.
CAUTION:
Coasting downhill in NEUTRAL (N) or with the
ignition off is dangerous. Your brakes will have to
do all the work of slowing down. They could get so
hot that they wouldn't work well. You would then
have poor braking or even none going down a hill.
You could crash. Always have your engine running
and your vehicle in gear when you go downhill.

Know how to go uphill. You may want to shift down
to a lower gear. The lower gears help cool your engine
and transmission, and you can climb the hill better.

Stay in your own lane when driving on two
-lane
roads in hills or mountains. Don't swing wide or cut
across the center of the road. Drive at speeds that let
you stay in your own lane.

As you go over the top of a hill, be alert. There could be
something in your lane, like a stalled car or an accident.

You may see highway signs on mountains that warn of
special problems. Examples are long grades, passing or
no
-passing zones, a falling rocks area or winding
roads. Be alert to these and take appropriate action.

4-51 If You Do Decide To Pull A Trailer
If you do, here are some important points:

There are many different laws, including speed limit
restrictions, having to do with trailering. Make sure
your rig will be legal, not only where you live but
also where you'll be driving. A good source for this
information can be state or provincial police.

Consider using a sway control if your trailer will
weigh less than the capacity stamped on your step
bumper. You should always use a sway control
if your trailer will weigh more than the capacity
stamped on your step bumper. You can ask a
hitch dealer about sway controls.

Consider using a sway control. You can ask a
hitch dealer about sway controls.

Don't tow a trailer at all during the first 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.

Then, during the first 500 miles (800 km) that you
tow a trailer, don't drive over 50 mph (80 km/h) and
don't make starts at full throttle. This helps your
engine and other parts of your vehicle wear in at
the heavier loads.
You should tow in DRIVE (D). You may want to
shift the transmission to THIRD (3) or, if necessary,
a lower gear selection if the transmission shifts too
often (e.g., under heavy loads and/or hilly conditions).
If you have a manual transmission and you are towing
a trailer, it's better not to use FIFTH (5) gear. Just
drive in FOURTH (4) gear (or, as you need to, a
lower gear). See ªTow/Haul Modeº in the Index.
Three important considerations have to do with weight:

the weight of the trailer,

the weight of the trailer tongue

and the weight on your vehicle's tires.
Tow/Haul Mode
Tow/haul is a feature that assists when pulling a heavy
trailer or a large or heavy load. The purpose of the
tow/haul mode is to:

Reduce the frequency and improve the predictability
of transmission shifts when pulling a heavy trailer or
a large or heavy load.

Provide the same solid shift feel when pulling a
heavy trailer or a large or heavy load as when the
vehicle is unloaded.

Improve control of vehicle speed while requiring less
throttle pedal activity when pulling a heavy trailer or
a large or heavy load.

4-57 Trailer Brakes
If your trailer weighs more than 2,000 lbs. (900 kg)
loaded, then it needs its own brakes
-- and they must
be adequate. Be sure to read and follow the instructions
for the trailer brakes so you'll be able to install, adjust
and maintain them properly.
Your trailer brake system can tap into the vehicle's
hydraulic brake system only if:

The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.

The trailer's brake system will use less than
0.02 cubic inches (0.3 cc) of fluid from your
vehicle's master cylinder. Otherwise, both braking
systems won't work well. You could even lose
your brakes.
If everything checks out this far, make the brake tap
at the port on the master cylinder that sends the fluid
to the rear brakes. But don't use copper tubing for this.
If you do, it will bend and finally break off. Use steel
brake tubing.
Driving with a Trailer
CAUTION:
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon monoxide
(CO) could come into your vehicle. You can't see
or smell CO. It can cause unconsciousness or
death. See ªEngine Exhaustº in the Index. To
maximize your safety when towing a trailer:

Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.

Keep the rear
-most windows closed.

If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle. Do not use
MAX A/C because it only recirculates the
air inside your vehicle. See ªComfort
Controlsº in the Index.