2007 GMC SIERRA cooling

Engine Fan Noise
If your vehicle has a clutched engine cooling fan,
when the clutch is engaged, the fan spins
faster to provide more air to cool the engine. In
most everyday driving conditions, the fan is
spinning slower and the clutch is not fully engaged.
This improves fuel economy and reduces fan
noise. Under heavy vehicle loading, trailer towing,
and/or high outside temperatures, the fan speed
increases as the clutch more fully engages, so you
may hear an increase in fan noise. This is
normal and should not be mistaken as the
transmission slipping or making extra shifts. It is
merely the cooling system functioning properly.
The fan will slow down when additional cooling is
not required and the clutch disengages.You may also hear this fan noise when you start
the engine. It will go away as the fan clutch
partially disengages.
If your vehicle has electric cooling fans, you may
hear the fans spinning at low speed during most
everyday driving. The fans may turn off if no cooling
is required. Under heavy vehicle loading, trailer
towing, and/or high outside temperatures, or if you
are operating your air conditioning system, the fans
may change to high speed and you may hear an
increase in fan noise. This is normal and indicates
that the cooling system is functioning properly. The
fans will change to low speed when additional
cooling is no longer required.
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Wheel Replacement
Replace any wheel that is bent, cracked, or badly
rusted or corroded. If wheel nuts keep coming
loose, the wheel, wheel bolts and wheel nuts
should be replaced. If the wheel leaks air, replace
it (except some aluminum wheels, which can
sometimes be repaired). See your dealer if any of
these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same
load-carrying capacity, diameter, width, offset
and be mounted the same way as the one
it replaces.
If you need to replace any of your wheels, wheel
bolts or wheel nuts, replace them only with
new GM original equipment parts. This way, you
will be sure to have the right wheel, wheel
bolts and wheel nuts for your vehicle.{CAUTION:
Using the wrong replacement wheels,
wheel bolts, or wheel nuts on your vehicle
can be dangerous. It could affect the
braking and handling of your vehicle,
make your tires lose air and make you
lose control. You could have a collision in
which you or others could be injured.
Always use the correct wheel, wheel bolts,
and wheel nuts for replacement.
Notice:The wrong wheel can also cause
problems with bearing life, brake cooling,
speedometer or odometer calibration,
headlamp aim, bumper height, vehicle ground
clearance, and tire or tire chain clearance
to the body and chassis.
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Fuses Usage
52 Rear Defogger
53 Heated Mirrors
54 SEO B1 Uptter Usage (Battery)
55 Cigarette Lighter, Auxiliary Power Outlet
56Automatic Level Control Compressor
Relay, SEO Uptter Usage
57 Climate Controls (Ignition)
58Engine Control Module, Secondary Fuel
Pump (Ignition)
J-Case Fuses Usage
59 Cooling Fan 1
60 Automatic Level Control Compressor
61 Heavy Duty Anti-lock Brake System
62 Cooling Fan 2
63 Anti-lock Brake System 1
64 Starter
65 Stud 2 (Trailer Brakes)
66 Left Bussed Electrical Center 1
67 Not Used
68 Heated Windshield Washer System
69 Four-Wheel Drive System
J-Case Fuses Usage
70Stud 1 (Trailer Connector Battery
Power) (Optional - 40A Fuse
Required)
71 Mid-Bussed Electrical Center 1
72 Climate Control Blower
73 Tailgate Open/Close Assist
74 Left Bussed Electrical Center 2
Relays Usage
FAN HI Cooling Fan High Speed
FAN LO Cooling Fan Low Speed
ENG EXH VLV Not Used
FAN CNTRL Cooling Fan Control
HDLP LO/HID Low-Beam Headlamp
FOG LAMP Front Fog Lamps
A/C CMPRSR Air Conditioning Compressor
STRTR Starter
PWR/TRN Powertrain
FUEL PMP Fuel Pump
PRK LAMP Parking Lamps
REAR DEFOG Rear Defogger
RUN/CRANK Switched Power
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Capacities and Specications
The following approximate capacities are given in English and metric conversions. SeeRecommended
Fluids and Lubricants on page 635for more information.
If your vehicle has the DURAMAX
®Diesel engine, see the DURAMAX®Diesel manual for more
information.
ApplicationCapacities
English Metric
Air Conditioning Refrigerant R134aFor the air conditioning system refrigerant charge
amount, see the refrigerant caution label located
under the hood. See your dealer for more
information.
Cooling System
4.3L V6 ** 16.5 qt 15.6 L
4.8L V8 ** 16.9 qt 16.0 L
5.3L V8 ** 16.9 qt 16.0 L
6.0L V8 * 16.4 qt 15.5 L
6.0L V8 ** 16.8 qt 15.9 L
* 2500, 3500 series
** 1500 series
Engine Oil with Filter
4.3L V6 4.5 qt 4.3 L
4.8L V8; 5.3L V8; 6.0L V8 6.0 qt 5.7 L
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Scheduled Maintenance (cont’d)
Service MaintenanceIMaintenanceII
Perform any needed additional services. See “Additional Required Services” in
this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transmission uid level and add uid as needed.•
Inspect shields, vehicles with diesel engine or with GVWR above
10,000 lbs (4 536 kg) only.See footnote (n).•
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Additional Required Services (cont’d)
Service and Miles (Kilometers)25,000
(40 000)50,000
(80 000)75,000
(120 000)100,000
(160 000)125,000
(200 000)150,000
(240 000)
Four-wheel drive only: Change transfer
case uid (extreme duty service).See
footnotes (g) (l) and (m).• •••••
Four-wheel drive only: Change transfer
case uid (normal service).See
footnotes (g) and (m).•••
Inspect evaporative control system.
An Emission Control Service. See
footnotes † and (k).•••
Replace spark plugs and inspect spark
plug wires.An Emission Control
Service.•
Engine cooling system service (or every
ve years, whichever occurs rst).
An Emission Control Service. See
footnote (i).•
Inspect engine accessory drive belt.
An Emission Control Service. See
footnote (q).•
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Maintenance Footnotes
(Gasoline Engine)
This maintenance section applies to vehicles with
a gasoline engine. If your vehicle has a diesel
engine, see the maintenance schedule section in
the DURAMAX
®Diesel Engine Supplement.
†The U.S. Environmental Protection Agency or
the California Air Resources Board has determined
that the failure to perform this maintenance item
will not nullify the emission warranty or limit
recall liability prior to the completion of the
vehicle’s useful life. We, however, urge that all
recommended maintenance services be performed
at the indicated intervals and the maintenance
be recorded.
#Lubricate the front suspension, steering linkage,
transmission shift linkage, and parking brake
cable guides. Control arm ball joints on 2500/3500
series vehicles require lubrication but should
not be lubricated unless their temperature is 10°F
(−12°C) or higher, or they could be damaged.
Control arm ball joints on 1500 series vehicles are
maintenance-free. Vehicles used under severe
commercial operating conditions require lubrication
on a regular basis every 3,000 miles (5 000 km).(a)Visually inspect brake lines and hoses for
proper hook-up, binding, leaks, cracks, chang,
etc. Inspect disc brake pads for wear and rotors for
surface condition. Inspect drum brake
linings/shoes for wear or cracks. Inspect other
brake parts, including drums, wheel cylinders,
calipers, parking brake, etc.
(b)Visually inspect front and rear suspension and
steering system for damaged, loose or missing
parts, signs of wear or lack of lubrication. Inspect
power steering lines and hoses for proper
hook-up, binding, leaks, cracks, chang, etc.
Visually check constant velocity joints, rubber
boots, and axle seals for leaks.
(c)Visually inspect hoses and have them replaced
if they are cracked, swollen, or deteriorated.
Inspect all pipes, ttings and clamps; replace with
genuine GM parts as needed. To help ensure
proper operation, a pressure test of the cooling
system and pressure cap and cleaning the outside
of the radiator and air conditioning condenser is
recommended at least once a year.
(d)Visually inspect wiper blades for wear or
cracking. Replace wiper blades that appear worn
or damaged or that streak or miss areas of
the windshield.
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(e)Make sure the safety belt reminder light and all
your belts, buckles, latch plates, retractors, and
anchorages are working properly. Look for
any other loose or damaged safety belt system
parts. If you see anything that might keep a safety
belt system from doing its job, have it repaired.
Have any torn or frayed safety belts replaced. Also
look for any opened or broken airbag coverings,
and have them repaired or replaced. The
airbag system does not need regular maintenance.
(f)Lubricate all key lock cylinders, body door
hinges, hood latch assembly, secondary latch,
pivots, spring anchor, release pawl, tailgate hinges,
tailgate linkage, tailgate handle pivot points,
latch bolt, fuel door hinge, locks, and folding seat
hardware. More frequent lubrication may be
required when exposed to a corrosive
environment. Applying silicone grease on
weatherstrips with a clean cloth will make them
last longer, seal better, and not stick or squeak.
(g)Check vent hose at transfer case for kinks and
proper installation. Check to be sure vent hose
is unobstructed, clear, and free of debris.(h)Change automatic transmission uid and lter
if the vehicle Gross Vehicle Weight Rating
(GVWR) is over 8600 lbs or if the vehicle is mainly
driven under one or more of these conditions:
In heavy city traffic where the outside
temperature regularly reaches 90°F (32°C) or
higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery
service.
(i)Drain, ush, and rell cooling system. This
service can be complex; you should have
your dealer perform this service. See Engine
Coolant on page 513 for what to use. Inspect
hoses. Clean radiator, condenser, pressure cap,
and ller neck. Pressure test the cooling
system and pressure cap.
(j)A uid loss in any vehicle system could indicate
a problem. Have the system inspected and
repaired and the uid level checked. Add uid if
needed.
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