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Temperature – A, B, C
The temperature grades are A (the highest), B,
and C, representing the tire’s resistance to
the generation of heat and its ability to dissipate
heat when tested under controlled conditions on a
specified indoor laboratory test wheel. Sustained
high temperature can cause the material of the tire
to degenerate and reduce tire life, and excessive
temperature can lead to sudden tire failure.
The grade C corresponds to a level of performance
which all passenger car tires must meet under
the Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent higher levels
of performance on the laboratory test wheel
than the minimum required by law.
Warning:The temperature grade for this tire is
established for a tire that is properly inflated
and not overloaded. Excessive speed,
underinflation, or excessive loading, either
separately or in combination, can cause heat
buildup and possible tire failure.
Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned
and balanced carefully at the factory to give you
the longest tire life and best overall performance.
Adjustments to wheel alignment and tire
balancing will not be necessary on a regular basis.
However, if you notice unusual tire wear or your
vehicle pulling to one side or the other, the
alignment may need to be checked. If you notice
your vehicle vibrating when driving on a smooth
road, your tires and wheels may need to be
rebalanced. See your dealer for proper diagnosis.
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.
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Underbody Maintenance
Chemicals used for ice and snow removal and
dust control can collect on the underbody. If these
are not removed, corrosion and rust can develop
on the underbody parts such as fuel lines,
frame, floor pan, fuel operated heater (FOH) and
exhaust system even though they have corrosion
protection.
At least every spring, flush these materials from
the underbody with plain water. Clean any
areas where mud and debris can collect. Dirt
packed in close areas of the frame should
be loosened before being flushed. Your dealer or
an underbody car washing system can do this
for you.
Chemical Paint Spotting
Some weather and atmospheric conditions can
create a chemical fallout. Airborne pollutants can
fall upon and attack painted surfaces on the
vehicle. This damage can take two forms: blotchy,
ring-shaped discolorations, and small, irregular
dark spots etched into the paint surface.
Although no defect in the paint job causes this,
GM will repair, at no charge to the owner, the
surfaces of new vehicles damaged by this fallout
condition within 12 months or 12,000 miles
(20 000 km) of purchase, whichever occurs first.
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Page 391 of 452
Fuse Usage
18 Truck Body Control Module 2
19 Truck Body Control Module
20 Remote Function Actuator
21 Engine 2 (Gas), Spare (Diesel)
22 Ignition E
23 Engine 1
24Truck Body Control Module
Ignition 1
25 Spare (Gas), Fuel Heater (Diesel)
26 Inside Rearview Mirror
27 Crankcase
28Brake Transmission Shift
Interlock System
29 Auxiliary Power Outlets
30 Cigarette Lighter
31 Instrument Panel Cluster
32 Air ConditioningFuse Usage
33Spare (Gas), Engine Control
Module (Diesel)
34Canister Vent Solenoid (Gas), Rear
Fog Lamps (Diesel)
35Spare (Gas & LLY Diesel), Fan
Clutch (LMM Diesel)
36Brake Transmission Shift Interlock,
Vehicle Back-Up
37 Airbag
38Powertrain Control Module Ignition 1
(Gas), Engine Control Module,
Transmission Control Module, Glow
Plug Control Module Ignition 1
(Diesel)
39Oxygen Sensor B (Gas),
Spare (Diesel)
40Oxygen Sensor A (Gas),
Spare (Diesel)
41 Windshield Wipers
42 Right Headlamp - Low Beam
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Fuse Usage
43 Left Headlamp - Low Beam
44 Left Headlamp - High Beam
45 Right Headlamp - High Beam
46Truck Body Controller- Accessory
(Gas), Truck Body Controller,
Transmission Control Module
Accessory (Diesel)
47 Front Windshield Wiper
48Anti-lock Brakes, Vehicle Stability
Enhancement System
49 Ignition A
50 Trailer
51 Climate Control Blower
52 Ignition B
63Spare (Gas), Engine Control Module
Actuator (Diesel)
64 SpareRelays Usage
53 Windshield Wiper
54 Air Conditioning
55Spare (Gas), Rear Fog Lamps
(Diesel)
56 Headlamp - High Beam
57 Fuel Pump
58 Headlamp - Low Beam
59 Horn
SPARE (G),
ECM (D)Spare (Gas), Engine Control
Module (Diesel)
STRTR Starter
Circuit Breaker Usage
PWR SEAT Power Seat
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