When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions,
influence when you need new tires.
One way to tell when it is
time for new tires is to
check the treadwear
indicators, which appear
when your tires have only
1/16 inch (1.6 mm) or less
of tread remaining.
Some commercial truck tires, including Goodyear
LT225/75R16 G949 RSA and Goodyear LT225/75R16
G933 RSD, may not have treadwear indicators. If the
tires do not have treadwear indicators, replace the tires
when the tread depth is down to 1/8 inch (3.2 mm) for
the front tires, or 1/16 inch (1.6 mm) for the rear tires.You need new tires if any of the following statements
are true:•You can see the indicators at three or more places
around the tire.
•You can see cord or fabric showing through the
tire’s rubber.
•The tread or sidewall is cracked, cut, or snagged
deep enough to show cord or fabric.
•The tire has a bump, bulge, or split.
•The tire has a puncture, cut, or other damage that
cannot be repaired well because of the size or
location of the damage.
The rubber in tires degrades over time, even if they are
not being used. This is also true for the spare tire, if your
vehicle has one. Multiple conditions affect how fast this
aging takes place, including temperatures, loading
conditions, and inflation pressure maintenance. With
proper care and maintenance tires will typically wear out
before they degrade due to age. If you are unsure about
the need to replace your tires as they get older, consult
the tire manufacturer for more information.
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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. It should be noted that
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 might need to be checked. If you notice your
vehicle vibrating when driving on a smooth road, the tires
and wheels might need to be rebalanced. See your
dealer/retailer 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/retailer if any of these conditions exist.
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Finish Damage
Any stone chips, fractures or deep scratches in the
finish should be repaired right away. Bare metal
will corrode quickly and may develop into major
repair expense.
Minor chips and scratches can be repaired with
touch-up materials available from your dealer/retailer.
Larger areas of finish damage can be corrected in
your dealer’s/retailer’s body and paint shop.
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,
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/retailer or an underbody car washing system
can do this.
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, we 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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Floor Console Fuse Block
The floor console fuse block is located under the
driver seat.
Mini-Fuse Usage
F1 Empty
F2 Steering Wheel Sensor
F3 Auxiliary Parking Lamps (Cut-Away)
F4 Front Park Lamps
F5 Trailer Park Lamps
F6 Upfitter Park Lamps
F7 Right Rear Park Lamp
F8 Left Rear Park Lamp
F9 Outside Rear View Mirror Switch
F10 Airbag/AOS
F11 Empty
F12 Empty
F13Heating, Ventilation and
Air Conditioning 2
F14Heating, Ventilation and
Air Conditioning 1
F15 Empty
F17 Outside Rear View Mirror Heater
F18 Rear Window Defogger
F19 Compass
F20 Radio/Chime
F21Remote Function Actuator/
Tire Pressure Monitor
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Mini-Fuse Usage
F22Ignition Switch/Discrete Logic
Ignition Sensor (PK3)
F23 Instrument Panel Cluster
F25Heating, Ventilation and
Air Conditioning Control
F26 Auxiliary/Trailer Backup
F27 Tail Lamps Backup
F30 Upfitter Courtesy Lamps
F31 Front Door Lock
F32 Rear Door Lock
F33 Cargo Door Unlock
F34 Passenger Door Unlock
F35 Rear Passenger Door Unlock
F36 Driver Door Unlock
F37 Empty
F38 Empty
J-Case Fuse Usage
F16 Upfitter Auxiliary 1
F24 Empty
F28 Upfitter Auxiliary 2 Reading Lamps
F29 Rear Blower
Relays Usage
K1 Run (High Current Micro)
K2 Empty (High Current Micro)
K3 Park Lamps (High Current Micro)
K4Upfitter Auxiliary 2
(High Current Mini)
K5 Rear Defogger (High Current Micro)
K6Retained Accessory Power (RAP)
(High Current Micro)
Circuit Breaker Usage
CB1 Power Seats
CB2 Power Windows
Engine Compartment Fuse Block
The fuse block is located in the engine compartment on
the driver side of the vehicle.
Notice:Spilling liquid on any electrical components
on the vehicle may damage it. Always keep the
covers on any electrical component.
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Mini Fuse Usage
3 Right Stop/Turn Trailer
4 Spare
5 Spare
6 Fuel System Control Module Ignition
7 Body Control Module 5
8 Body Control Module 7
9 Body Control Module 4
10 Instrument Panel Cluster
11 Trailer Wiring
12 Spare
13 Brake Switch
14 Windshield Washer
16 Horn
17 Transmission
18 Air Conditioning Compressor
19 Engine Control Module Battery
20 Spare
21 Left Stop/Turn Trailer
22 Spare
23 Spare
24 Fuel Pump
25 Auxiliary Power Outlet
26 Body Control Module 3
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J-Case Fuse Usage
1 ABS Motor
2 ABS Module
41 Spare
42 Trailer Wiring
43 Fan High
44 Starter Solenoid
45 Engine Control Module/Powertrain
46 Fuel System Control Module Battery
47 Fan Lo
74 Front BlowerRelay Usage
15 Run/Crank
37 Spare
38 Fuel Pump
39 Crank
40 Air Conditioning Compressor
48 Fan High
49 Powertrain
50 Fan Clutch (EV)
57 Fan Low
60 Fan Control
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