Page 345 of 452
A CAUTION:
Rust or dirt on a wheel, or on the parts to which
it is fastened, can make wheel nuts become loose
after a 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 you
need to, to get all the rust
or dirt off. (See
“Changing
a Flat Tire” in the Index.)
1 When It’s Time for New Tires
One way to tell when it’s
time for new tires is to
check the treadwear
indicators, which will
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.
6-55
ProCarManuals.com
Page 368 of 452

Normal Maintenance Replacement Parts
Replacement part numbers listed in this section are based on the latest information available at the time of printing,
and are subject to change. If a part listed
in this manual is not the same as the part used in your vehicle when it was
built, or
if you have any questions, please contact your GM truck dealer.
These specifications are for information only.
If you have any questions, see the service manual for the chassis or
refer
to the body manufacturer's publications.
VIN Code
Oil Filter';"
Air Cleaner Filter*
PCV Valve*
Spark Plugs*
Fuel Filter*
Wiper Blades**
Wiper Blade Type
Wiper Blade Length
w M
PF52 PF12 18.1
A 1300C??
A 1300C??
CV746C CV796C
4 1-932 4 1-932
GF626 GF626
22154886 22 154886
Trico Trico
18 inches (45.0 cm) 18 inches
(45.0 cm)
"AC part number
**GM part number
?Use
a PF52 oil filter if your vehicle has four-wheel drive.
??A1301C high-capacity air cleaner filter.
R J
PF1218? PF1218
A 1300C?? A 1300C??
CV796C cv774c
4 1-932 4 1-932
GF626 GF626
22 154886 22154886
Trico Trico
18 inches (45.0 cm) I8
inches (45.0 cm)
6-78
ProCarManuals.com
Page 379 of 452

1 Short Trip/City Maintenance Schedule -- Gasoline Engines I
4:::: Drive axle service (see "Recommended Fluids and
Lubricants"
in the Index for proper lubricant to use):
0 Locking Differential -- Drain fluid and refill at first
engine oil change. At subsequent oil changes, check
fluid level and add fluid as needed.
If driving in
dusty areas or towing a trailer, drain fluid and refill
every
15,000 miles (25 000 km).
Standard Differential -- Check fluid level and add
fluid as needed at every oil change.
If driving in
dusty areas or towing a trailer. drain fluid and refill
every 15,000 miles (25
000 km).
More frequent lubrication may be required for
0 3500 HD Models with applications requiring
heavy-duty
or off-road use.
extreme overload/trailer towing conditions and
high-speed (above
45 mph or 70 km/h) conditions
for extended periods of time must have the drive axle
fluid changed every
30,000 miles (50 000 km).
See "Recommended Fluids and Lubricants" in
this section.
7-9
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Page 398 of 452

Long TripMighway Maintenance Schedule =- Gasoline Engines
The services shown in this schedule up to 100,000 miles
(166 000 km) should be performed after 100,000 miles
(166 000 km) at the same intervals. The services shown
at 150,000 miles (240 000
km) should be performed at
the same interval after 150,000 miles (240 000 km).
See “Owner Checks and Services” and “Periodic Maintenance Inspections” following.
Footnotes
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, kingpin bushings,
steering linkage, transmission
shift linkage, transfer case
shift linkage, parking brake cable guides, rear driveline
center splines, front axle propshaft spline and brake
pedal springs. Ball joints and kingpin bushings should
not be lubricated unless their temperature is 10°F
(- 12°C) or higher, or they could be damaged.
+ A good time to check your brakes is during tire
rotation. See “Brake System Inspection” under “Periodic
Maintenance Inspections”
in Part C of this schedule.
‘+‘K Drive axle service (see “Recommended Fluids and
Lubricants”
in the Index for proper lubricant to use):
Locking Differential -- Drain fluid and refill at first
engine oil change.
At subsequent oil changes, check
fluid level and add fluid as needed.
0 Standard Differential -- Check fluid level and add
fluid
as needed at every engine oil change.
3500 HD Models with applications requiring
high-speed (above 45 mph or 70 kndh) operation
for
extended periods of time must have the drive axle
fluid changed every 30,000 miles
(50 000 km).
7-28
ProCarManuals.com
Page 428 of 452

Courtesy Transportation
GMC Commitment Plus offers courtesy transportation
for customers when obtaining warranty service.
This program is offered in conjunction with the
3 year/36,000 mile (60 000 km) Bumper to Bumper
New Vehicle Limited Warranty.
Courtesy transportation includes:
0
0
0
One way shuttle ride from the dealership (up to
10 miles (16 km)) for same-day warranty repairs.
A loaner vehicle will be made available for overnight
warranty repairs
up to a five day maximum, or up to a
$30 allowance for a rental vehicle, cab, bus or other
transportation
in lieu of a loaner. (Bringing vehicles in
late in the day, for service on the next day. c10c.s not
constitute overnight repairs.)
Gas allowance
of up to $10 a day for rides provided
by another person (i.e., friend, neighbor, etc.)
in
lieu of rental for overnight warranty repair up to a
five day maximum. Some
state insurance regulations make
it impractical
to rent vehicles to people under
2 1 years of age. If
you are under 2 1 and have difficulty renting a vehicle,
GMC
will reimburse up to $30/day for documented
transportation
you receive.
The Commitment Plus Courtesy Transportation Program is not part of the Bumper to Bumper Limited Warranty.
GMC reserves the right to make any changes or
discontinue the Courtesy Transportation Program at any
time without notification.
For additional program details, contact your GMC dealer.
In Canada, please consult your GM dealer for
information on Courtesy Transportation.
8-8
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Page 433 of 452

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'M EST) information within 30 days of delivery. On returns, a re-stocking fee may be applied
i927 against the original order.
ITEM DESCRIPTION , VEHICLE MODEL PRICE QTY' EACH*
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Service Manual I 1998 I I $90.00 I
Car & Light Truck
Transmission Unit Repair 1998 $40.00
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NOTE: Dealers and Companies please provide dealer or company name. and also the
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