2007 GMC YUKON XL maintenance

Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is
designed to remain in your vehicle for ve years or
150,000 miles (240 000 km), whichever occurs
rst, if you add only DEX-COOL
®extended
life coolant.
The following explains your cooling system and
how to add coolant when it is low. If you have
a problem with engine overheating, seeEngine
Overheating on page 452.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to
−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they
should.
Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant may require changing sooner, at
the rst maintenance service after each
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would not
be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your
vehicle.
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Brakes
Brake Fluid
Your brake master
cylinder reservoir is
lled with DOT-3 brake
uid. SeeEngine
Compartment Overview
on page 436for the
location of the reservoir.
There are only two reasons why the brake uid
level in the reservoir might go down. The rst
is that the brake uid goes down to an acceptable
level during normal brake lining wear. When
new linings are put in, the uid level goes back
up. The other reason is that uid is leaking out of
the brake system. If it is, you should have your
brake system xed, since a leak means that
sooner or later your brakes will not work well, or
will not work at all.So, it is not a good idea to top off your brake uid.
Adding brake uid will not correct a leak. If you
add uid when your linings are worn, then you will
have too much uid when you get new brake
linings. You should add or remove brake uid, as
necessary, only when work is done on the
brake hydraulic system.
{CAUTION:
If you have too much brake uid, it can
spill on the engine. The uid will burn if
the engine is hot enough. You or others
could be burned, and your vehicle could
be damaged. Add brake uid only when
work is done on the brake hydraulic
system. See “Checking Brake Fluid” in
this section.
When the brake uid falls to a low level, the brake
warning light will come on. SeeBrake System
Warning Light on page 232.
Refer to the Maintenance Schedule to determine
when to check your brake uid. SeeScheduled
Maintenance on page 555.
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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. Your vehicle was designed and tested
with top-quality GM brake parts. When you replace
parts of your braking system — for example,
when your brake linings wear down and you need
new ones put in — be sure you get new
approved GM replacement parts. If you do not,
your brakes may no longer work properly. For
example, if someone puts in brake linings that are
wrong for your vehicle, the balance between your
front and rear brakes can change — for the worse.
The braking performance you have come to expect
can change in many other ways if someone puts in
the wrong replacement brake parts.
Battery
Your vehicle has a maintenance free battery.
When it is time for a new battery, get one that has
the replacement number shown on the original
battery’s label. We recommend an ACDelco
®
replacement battery. SeeEngine Compartment
Overview on page 436for 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
If you are not going to drive your vehicle for
25 days or more, remove the black,
negative (−) cable from the battery. This will
help keep your battery from running down.
{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 467for tips on working
around a battery without getting hurt.
466

When to Change Lubricant
Refer to the Maintenance Schedule to determine
how often to change the lubricant. See
Scheduled Maintenance on page 555.
What to Use
Refer to the Maintenance Schedule to determine
what kind of lubricant to use. SeeRecommended
Fluids and Lubricants on page 564.
Front Axle
When to Check and Change Lubricant
It is not necessary to regularly check front axle
uid unless you suspect there is a leak or you hear
an unusual noise. A uid loss could indicate a
problem. Have it inspected and repaired.
How to Check Lubricant
To get an accurate reading, the vehicle should be
on a level surface.
If the level is below the bottom of the ller plug
hole, located on the front axle, you may need
to add some lubricant:
When the differential is cold, add enough
lubricant to raise the level from 0 (0 mm)
to 1/8 inch (3.2 mm) below the ller plug hole.
When the differential is at operating
temperature (warm), add enough lubricant to
raise the level to the bottom of the ller
plug hole.
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What to Use
Refer to the Maintenance Schedule to determine
what kind of lubricant to use. SeeRecommended
Fluids and Lubricants on page 564.
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 an accident,
the aim of the headlamps may be affected and
adjustment may be necessary.
If oncoming vehicles ash 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 in the following
procedure.The vehicle should be properly prepared as
follows:
The vehicle should be placed so the
headlamps are 25 ft. (7.6 m) from a light
colored wall.
The vehicle must have all four tires on a level
surface which is level all the way to the wall.
The vehicle should be placed so it is
perpendicular to the wall.
The vehicle should not have any snow, ice, or
mud on it.
The vehicle should be fully assembled and all
other work stopped while headlamp aiming is
being performed.
The vehicle should be normally loaded with
a full tank of fuel and one person or
160 lbs (75 kg) sitting on the driver’s seat.
Tires should be properly inated.
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.
475

Replacement Bulbs
Exterior Lamp Bulb Number
Back-up Lamp 7441
License Plate Lamp 168
Rear Turn Signal Lamp, Taillamp,
and Stoplamp3057
For replacement bulbs not listed here, contact
your dealer.
Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for
wear or cracking. SeeScheduled Maintenance
on page 555.
Replacement blades come in different types and
are removed in different ways. To replace the
wiper blade assembly, do the following:
1. Pull the windshield wiper arm connector away
from the windshield.
2. Squeeze the grooved areas on each side of
the blade, and rotate the blade assembly
away from the arm connector.
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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, seeNormal
Maintenance Replacement Parts on page 566.
Backglass Wiper Blade Replacement
1. 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.
2. Rotate the wiper blade assembly, then push it
from the wiper arm.
3. Replace the wiper blade.
Tires
Your newvehicle comes with high-quality tires made
by a leading tire manufacturer. If you ever have
questions about your tire warranty and where to
obtain service, see your GM Warranty booklet for
details. For additional information refer to the tire
manufacturer’s booklet included with your vehicle.
482

For additional information and details about the
DIC operation and displays seeDIC Operation and
Displays (With DIC Buttons) on page 244orDIC
Operation and Displays (Without DIC Buttons)
on page 251andDIC Warnings and Messages on
page 254.
You may notice, during cooler weather conditions,
that the tire pressure monitor light, located on
the instrument panel cluster, and the CHECK TIRE
PRESSURE message will appear when the
vehicle is rst started and then turn off as you
start to drive the vehicle. This could be an early
indicator that the tire pressures are getting low and
need to be inated to the proper pressure.
Each tire, including the spare (if provided), should
be checked monthly when cold and inated to
the ination pressure recommended by the vehicle
manufacturer on the vehicle placard or tire
ination pressure label. (If your vehicle has tires of
a different size than the size indicated on the
vehicle placard or tire ination pressure label, you
should determine the proper tire ination
pressure for those tires.)As an added safety
feature, your vehicle has
been equipped with a
tire pressure monitoring
system (TPMS) that
illuminates a low tire
pressure telltale when
one or more of your tires
is signicantly
under-inated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires
as soon as possible, and inate them to the
proper pressure. Driving on a signicantly
under-inated tire causes the tire to overheat and
can lead to tire failure. Under-ination also
reduces fuel efficiency and tire tread life, and may
affect the vehicle’s handling and stopping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the driver’s
responsibility to maintain correct tire pressure,
even if under-ination has not reached the level to
trigger illumination of the TPMS low tire pressure
telltale.
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