2007 GMC SIERRA maintenance

When to Inspect the Engine Air
Cleaner/Filter
If your vehicle has an air lter restriction indicator,
it lets you know when the engine air cleaner/lter
needs to be replaced. On vehicles with a restriction
indicator, you should inspect the air lter
restriction indicator at every oil change and
replace the engine air cleaner/lter when the
indicator tells you to.
On vehicles without an air lter restriction indicator,
inspect the air cleaner/lter at the MaintenanceII
intervals and replace it at the rst oil change
after each 50,000 mile (83 000 km) interval. See
Scheduled Maintenance (Gasoline Engine) on
page 623for more information. If you are driving
in dusty/dirty conditions, inspect the lter at
each engine oil change.
How to Inspect the Engine Air
Cleaner/Filter
Vehicles With an Air Filter Restriction
Indicator
Locate the air lter restriction indicator on the
engine air cleaner/lter cover. When the indicator
turns black or is in the red/orange “change”
zone, replace the lter and reset the indicator. See
Steps 1 through 7 to replace the engine air
cleaner/lter and to reset the air lter restriction
indicator.
Vehicles Without an Air Filter Restriction
Indicator
To inspect the air cleaner/lter, remove the engine
air cleaner/lter from the vehicle by following
Steps 1 through 7. When you have the engine air
cleaner/lter removed, lightly shake it to release
loose dust and dirt. If the engine air cleaner/lter
remains caked with dirt, a new lter is required.
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5. Inspect or replace the engine air cleaner/lter.
6. Reinstall the cover and tighten the screws.
7. Reset the air lter restriction indicator, if
the vehicle has one, by pressing the top button
on the indicator.
{CAUTION:
Operating the engine with the air
cleaner/lter off can cause you or others
to be burned. The air cleaner not only
cleans the air; it helps to stop ames if
the engine backres. If it is not there and
the engine backres, you could be
burned. Do not drive with it off, and be
careful working on the engine with the air
cleaner/lter off.
Automatic Transmission Fluid
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 dealership service department and have it
repaired before driving the vehicle further.
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 inRecommended
Fluids and Lubricants on page 635.
Change the uid and lter at the intervals listed in
the Maintenance Schedule. SeeScheduled
Maintenance (Gasoline Engine) on page 623.Be
sure to use the transmission uid listed in
Recommended Fluids and Lubricants on page 635.
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Engine Coolant
If your vehicle has the DURAMAX®Diesel engine,
see the DURAMAX®Diesel manual for more
information.
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 516.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
The brake master
cylinder reservoir is
lled with DOT-3 brake
uid. SeeEngine
Compartment Overview
on page 498for 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 the
brake system xed, since a leak means that
sooner or later the brakes will not work well.So, it is not a good idea to top off the brake uid.
Adding brake uid will not correct a leak. If
you add uid when the 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.
Refer to the Maintenance Schedule to determine
when to check the brake uid. SeeScheduled
Maintenance (Gasoline Engine) on page 623.
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Brake Wear
Your vehicle has front disc brakes and could have
rear drum brakes or rear 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 your vehicle is moving, except when you
are pushing on the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon the brakes will not work well. That
could lead to an accident. When you hear
the brake wear warning sound, have your
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 rst 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
specications inCapacities and Specications on
page 616.
If you have rear drum brakes, they do not have
wear indicators, but if you ever hear a rear brake
rubbing noise, have the rear brake linings
inspected immediately. Rear brake drums should
be removed and inspected each time the tires
are removed for rotation or changing. Drum brakes
have an inspection hole to inspect lining wear
during scheduled maintenance. When you have
the front brake pads replaced, have the rear
brakes inspected, too.
Brake linings should always be replaced as
complete axle sets.
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Brake Pedal Travel
See your dealer/retailer 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 time you make a brake stop, the brakes
adjust for wear.
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 brake parts. When you replace
parts of the braking system — for example, when
the brake linings wear down and you need
new ones put in — be sure you get new approved
replacement parts. If you do not, the brakesmight not work properly. For example, if someone
puts in brake linings that are wrong for your
vehicle, the balance between the 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 498for 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.
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For all 6.0L 1500 Series applications, the proper
level is from 0.6 inches to 1.6 inches (15 mm to
40 mm) below the bottom of the ller plug hole,
located on the rear axle. Add only enough uid to
reach the proper level.
For all 6.0L 2500HD Series applications, the proper
level is from 0 to 0.5 inches (0 mm to 13 mm) below
the bottom of the ller plug hole, located on the
rear axle. Add only enough uid to reach the
proper level.
For all 6.6L Duramax Diesel 2500HD Series
applications and all 3500 Series applications, the
proper level is from 0.6 inches to 0.8 inches
(17 mm to 21 mm) below the bottom of the ller
plug hole, located on the rear axles. Add only
enough uid to reach the proper level.
What to Use
Refer to the Maintenance Schedule to determine
what kind of lubricant to use. SeeRecommended
Fluids and Lubricants on page 635.
Four-Wheel Drive
Lubricant checks in this section also apply to
these vehicles.
Transfer Case
When to Check Lubricant
It is not necessary to regularly check transfer case
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
A. Fill Plug
B. Drain Plug
Electric Shift Transfer Case
539

When to Change Lubricant
Refer to the Maintenance Schedule to determine
how often to change the lubricant. See
Scheduled Maintenance (Gasoline Engine) on
page 623.
What to Use
Refer to the Maintenance Schedule to determine
what kind of lubricant to use. SeeRecommended
Fluids and Lubricants on page 635.
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.
A. Fill Plug
B. Drain Plug
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