Page 264 of 374
Single Axle Models
Item Number Item Remarks
1 Brake Camshaft** One fitting each (apply sparingly).
2 Steering Column Slip Joint* One fitting.
3 Steering Drag Link Ends One fitting each end.
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Item Number Item Remarks
4 Pivot Points and Hinges Apply chassis lubricant.
5 Pivot Points and Hinges Apply chassis lubricant.
6 Slack Adjuster** One fitting.
7Brake Cam Roller Pins at interface
of pin and shoe**Apply engine oil.
8 Front Steering KnucklesOne fitting each side, lower bushing.
(Hand-operated grease gun only.)
Hand-pack upper bearing.
9 Front Wheel Bearings Hand-pack or lubricate.
10 Steering Tie Rod Ends One fitting each end.
11 Spring Slip Pads* (Multi-Leaf Only) Apply chassis lubricant.
12 Clutch Release Bearing* Cup or fitting.
13 Battery Terminal (except “ST” type) Keep coated with petroleum jelly.
14 Transmission Fill to level of filler plug.
15 Propshaft U-JointsLubricate with GM Part No. 1051344 Wheel
Bearing Lubricant.
16 Parking Brake Clevis Pin$ Apply chassis lubricant.
17 Parking Brake Lever Pivot*, $ Apply chassis lubricant.
18Clutch Release Cross Shaft,
Master Cylinder$Apply chassis lubricant, fill to 1/4 inch (6 mm)
below opening.
19 Release Bearing, Clutch Cross Shaft Two fittings, apply chassis lubricant.
20 Clutch Release Fork Two fittings.
* Applies to some vehicles.
** Applies to air brakes only.
$ Applies to hydraulic brakes only.
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Tandem Axle ModelsItem
Number Item Remarks
1 Brake Camshafts One fitting each.
2 Propshaft U-JointOne fitting each
joint. Lubricate with
GM Part
No. 1051344, Wheel
Bearing Lubricant
3 Rear AxlesFill to level of
filler plug.
4Brake Shoe
Roller PinsApply engine oil
at pin to shoe
joint only.
5 Rear Spring PinOne fitting
each side.
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2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles are not touching
each other. If they are, it could cause a ground
connection you do not want. You would not be able
to start your vehicle, and the bad grounding
could damage the electrical systems.
To avoid the possibility of the vehicles rolling, set the
parking brake firmly on both vehicles involved in the
jump start procedure. Put an automatic transmission
in PARK (P) or a manual transmission in NEUTRAL
before setting the parking brake. If you have a
four-wheel-drive vehicle, be sure the transfer case is
in a drive gear, not in NEUTRAL.
Notice:If you leave your radio or other accessories
on during the jump starting procedure, they could
be damaged. The repairs would not be covered
by your warranty. Always turn off your radio and
other accessories when jump starting your vehicle.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets. Turn off the
radio and all lamps that are not needed. This will
avoid sparks and help save both batteries, and
it could save the radio!4. Open the hood on the other vehicle and locate the
positive (+) and the negative (−) terminal locations
on that vehicle.
Open the hood on your
vehicle and find the remote
positive (+) terminal,
located under a red plastic
cover on the passenger’s
side of the vehicle.
Squeeze the tab to open
the cover and access
the remote positive (+)
terminal.
You will not see the battery (or batteries) of your
vehicle under the hood. They are located in a frame
mounted battery box, which is located on either
the driver’s or the passenger’s side of the vehicle.
You will not need to access your battery (or
batteries) for jump starting. The remote positive (+)
terminal is for that purpose.
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Wheel Replacement
Replace any wheel that is bent, cracked or badly rusted
or corroded. If wheel nuts keep coming loose, replace
the wheel. If the wheel leaks air, replace it.
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:
A leaking wheel could fail without warning. A
wheel designed for tubeless tires could be
leaking because it is damaged. Do not use an
inner tube or some other thing to try to stop the
leaking. Get a new wheel or the proper type.
{CAUTION:
Without the correct wheel, you may not be able
to stop properly, and you could have other
problems like a tire air-out. You could have a
collision. If you do not go to your dealer to get
a new wheel, be sure you get the correct one.
Each new wheel should match the original
wheel in load-carrying capacity, in ation
pressure capacity, diameter, width, offset and
mounting con guration.
Using wheels and tires with higher load-carrying limits
than the original wheels and tires does not change
the Gross Axle Weight Rating (GAWR) or the Gross
Vehicle Weight Rating (GVWR) of your vehicle.
SeeLoading Your Vehicle on page 4-32for more
information.
Notice:The wrong wheel can cause trouble in
bearing life, brake cooling, speedometer/odometer
calibration, headlamp aim, bumper height, vehicle
ground clearance, stopping distance and tire
clearance to the body and chassis. You could also
have other problems like a tire air-out.
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Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You cannot know how it has been
used or how far it has been driven. It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving,
especially if you maintain your tires properly. If air
goes out of a tire, it’s much more likely to leak out
slowly. But if you should ever have a “blow out,” here
are a few tips about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use
in a skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop –– well off the road if possible.
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place and turn on your
hazard warning flashers.
{CAUTION:
Your vehicle, when new, did not include tire
changing equipment or a place to store a tire
in the vehicle. Special tools and procedures
are required if a tire needs to be serviced. If
these tools and procedures are not used, you
or others could be injured or killed while trying
to change or service a truck tire.
Your truck, when new, did not include tire changing
equipment or a place to store a tire in the vehicle. Few
drivers of these vehicles have the necessary equipment
aboard to be able to change a flat tire safely.
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Fusible Links
A fusible link is a short piece of wire several gauge
sizes smaller than the circuit it protects. It will melt in an
overload situation, opening the circuit.
Your starter and other circuits have these fusible links.
The size is printed on the insulation. If the insulation
is burned beyond recognition, consult your GM dealer
for the proper size. Replace a fusible link with one of the
same size and insulation type. Fusible link insulation
is a special purpose high-temperature material.
The hydraulic brake booster motor feed circuit and
starter circuit are protected by a fusible link. Vehicles
with a diesel engine have a fusible link for the intake
heater feed circuit.
Power Windows and Other
Power Options
Circuit breakers in the fuse panel protect the power
windows and other power accessories. When the current
load is too heavy, the circuit breaker opens. This
protects the circuit until the current load returns to
normal or the problem is fixed.
Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from
short circuits by a combination of fuses, circuit breakers,
maxi-fuses and fusible links. This greatly reduces the
chance of a fire caused by an electrical problem. There
may be a fuse taped to the wiring harness near the
hydraulic brake booster.
Instrument Panel Fuse Block
There are two instrument panel fuse blocks located
behind the instrument panel on the passenger’s side of
the vehicle.
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Circuit Breaker Usage
16 Air Bag System
17 Exterior/Interior Lamps
18 Parking Brake
19 Accessory Power
20 Ignition 4
21 Sidemarker Lamps
22 Turn Signal/Backup Lamps
23 Transmission
24 Hydraulics/Air Brake
A Spare
B Spare
Fuse Usage
HTD/MIRR Heated Mirrors
Blank Not Used
RT TRN TRLR Trailer Right Turn Signal
Blank Not Used
LT TRN TRLR Trailer Left Turn Signal
Blank Not Used
BRK Brake Warning Lamp
RT PRK Right-hand Parking Lamps
Blank Not Used
Blank Not Used
Fuse Usage
Blank Not Used
LT PARK Left-hand Parking Lamps
Blank Not Used
RT REAR
TRN/STOPRight Rear Turn Signal/Stoplamp
LT REAR
TRN/STOPLeft Rear Turn Signal/Stoplamp
RADIO Radio
Blank Not Used
Blank Not Used
Blank Not Used
PWR WNDW Power Windows
Relay Usage
ECU/PTO*Engine Control Unit/Power Take-Off
Diesel 7.8 DURAMAX
®
BRK LAMPC4/C5 Brake Lamps,
C6/C7/C8 Tractor/Trailer Wiring
DRL Daytime Running Lamps
IGN-4 Ignition
CHMSL Center High Mounted Stop Lamp
MRK LTS Sidemarker and Clearance Lamps
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