Page 493 of 596

Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and Specifications on page 5-129.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the
vehicle. In an emergency, you can use a
cloth or a paper towel to do this; but be sure
to use a scraper or wire brush later, if
needed, to get all the rust or dirt off. See
Changing a Flat Tire on page 5-92.
If your vehicle has a Tire Pressure Monitor
System (TPMS), reset the TPMS sensors after
rotating the tires. SeeTire Pressure Monitor
Operation on page 5-77.
Make sure the spare tire, if your vehicle has one,
is stored securely. Push, pull, and then try to
rotate or turn the tire. If it moves, tighten the cable.
SeeStoring a Flat or Spare Tire and Tools on
page 5-109.
When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions,
in uence 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 may not have
treadwear indicators.
5-83
Page 499 of 596

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.
Your dealer/retailer 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 the wheels, wheel bolts,
wheel nuts or Tire Pressure Monitor System (TPMS)
sensors, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts, wheel nuts, and TPMS sensors
for the 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.
Whenever a wheel, wheel bolt or wheel nut is replaced
on a dual wheel setup, check the wheel nut torque after
100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km)
of driving. For proper torque, see “Wheel Nut Torque”
underCapacities and Specifications on page 5-129.
SeeChanging a Flat Tire on page 5-92for more
information.
5-89
Page 515 of 596

{CAUTION:
Incorrect or improperly tightened wheel nuts can
cause the wheel to come loose and even come
off. This could lead to a crash. If you have to
replace them, be sure to get new original
equipment wheel nuts. Stop somewhere as soon
as you can and have the nuts tightened with a
torque wrench to the proper torque speci cation.
SeeCapacities and Specifications on page 5-129
for wheel nut torque speci cation.
Notice:Improperly tightened wheel nuts can lead
to brake pulsation and rotor damage. To avoid
expensive brake repairs, evenly tighten the wheel
nuts in the proper sequence and to the proper
torque speci cation. SeeCapacities and
Specifications on page 5-129for the wheel nut
torque speci cation.12. Tighten the nuts rmly in a crisscross sequence as
shown by turning the wheel wrench clockwise.
When you reinstall the regular wheel and tire, you must
also reinstall either the center cap, or bolt-on hub cap,
depending on what your vehicle is equipped with. For
center caps, place the cap on the wheel and tap it into
place until it seats ush with the wheel. The cap only
goes on one way. Be sure to line up the tab on the center
cap with the indentation on the wheel. For bolt-on hub
caps, align the plastic nut caps with the wheel nuts and
then tighten by hand. Then use the wheel wrench to
tighten.
5-105
Page 540 of 596
ApplicationCapacities
English Metric
Fuel Tank
1500 Series Standard and Short Box 26.0 gal 98.0 L
1500 Series Long Box 34.0 gal 128.7 L
2500 Series Standard Box 26.0 gal 98.0 L
2500 Series and 3500 Series Long Box 34.0 gal 128.7 L
3500 Series Chassis Cab 50.0 gal 189.0 L
3500 Chassis Cab – Front Tank 27.0 gal 102.0 L
3500 Chassis Cab – Rear Tank (if equipped) 23.0 gal 87.0 L
Transmission Fluid (Pan Removal and Filter Replacement)
Auto 4-Speed Transmission 4L60-E Electronic
Transmission5.0 qt 4.7 L
Auto 6-Speed Transmission 6L80-E 6.0 qt 5.7 L
Auto 6-Speed Transmission 6L90-E 6.3 qt 6.0 L
Auto 6-Speed Transmission Allison 7.4 qt 7.0 L
Transfer Case Fluid 1.6 qt 1.5 L
Wheel Nut Torque 140 ft lb 190Y
All capacities are approximate. When adding, be sure to ll to the approximate level, as recommended in this
manual. Recheck uid level after lling.
5-130
Page 553 of 596

(n)Vehicles with diesel engine or with GVWR above
10,000 lbs (4 536 kg) only: Inspect shields for damage or
looseness. Adjust or replace as required. This is a Noise
Emission Control Service. Applicable to vehicles sold in
the United States and recommended for vehicles sold in
Canada.
(p)If driving regularly under dusty conditions, inspect
the filter or change indicator (if equipped) at each engine
oil change.
(q)Visually inspect belt for fraying, excessive cracks, or
obvious damage. Replace belt if necessary.
Owner Checks and Services
These owner checks and services should be performed
at the intervals speci ed to help ensure vehicle safety,
dependability, and emission control performance. Your
dealer/retailer can assist with these checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to the
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-15.
At the First 100, 1,000 and
6,000 Miles (160, 1 600 and
10 000 km)
For vehicles with dual wheels, check dual wheel nut
torque. For proper torque, seeCapacities and
Specifications on page 5-129.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel fill.
Engine Oil Level Check
Notice:It is important to check the engine oil
regularly and keep it at the proper level. Failure to
keep the engine oil at the proper level can cause
damage to the engine not covered by the vehicle
warranty.
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-15.
6-11