
yellowblue
6-15
CAUTION:
Operating the engine with the air cleaner/filter
off can cause you or others to be burned. The air
cleaner not only cleans the air, it stops flame if
the engine backfires. If it isn't there, and the
engine backfires, you could be burned. Don't
drive with it off, and be careful working on the
engine with the air cleaner/filter off.
NOTICE:
If the air cleaner/filter is off, a backfire can cause
a damaging engine fire. And, dirt can easily get
into your engine, which will damage it. Always
have the air cleaner/filter in place when
you're driving.
Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change both the fluid and filter every 15,000 miles
(25 000 km) if the vehicle is mainly driven under one or
more of these conditions:
In heavy city traffic where the outside temperature
regularly reaches 90F (32C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
If you do not use your vehicle under any of these
conditions, change the fluid and filter every
50,000 miles (83 000 km).
See ªScheduled Maintenance Servicesº in the Index.
ProCarManuals.com

yellowblue
6-30
Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
your brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly torque wheel nuts in the
proper sequence to GM specifications.
Brake linings should always be replaced as complete
axle sets.
See ªBrake System Inspectionº in Section 7
of this manual under Part C ªPeriodic
Maintenance Inspections.º
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in pedal
travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. Your vehicle
was designed and tested with top
-quality GM brake
parts. When you replace parts of your braking
system
-- for example, when your brake linings wear
down and you have to have new ones put in
-- be sure
you get new approved GM replacement parts. If you
don't, your brakes may no longer work properly. For
example, if someone puts in brake linings that are wrong
for your vehicle, the balance between your front and
rear brakes can change
-- for the worse. The braking
performance you've come to expect can change in many
other ways if someone puts in the wrong replacement
brake parts.
ProCarManuals.com

yellowblue
6-40
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
ªChanging a Flat Tireº in the Index.)
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.
You need a new tire 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
can't be repaired well because of the size or location
of the damage.
ProCarManuals.com

yellowblue
6-61
Air Conditioning Refrigerants
Not all air conditioning refrigerants are the same.
If the air conditioning system in your vehicle needs
refrigerant, be sure the proper refrigerant is used.
If you're not sure, ask your dealer.
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 GMC dealer.
Thermostat 12559051. . . . . . . . . . . . . . . . . . . . . . . . .
Oil Filter PF52. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Cleaner Filter A1163C. . . . . . . . . . . . . . . . . . . . . .
PCV Valve CV769C. . . . . . . . . . . . . . . . . . . . . . . . . .
Automatic Transmission Filter Kit 24200796. . . . . .
Spark Plugs 41
-932 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Filter GF481. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Windshield
Wiper Blade Trico (20 inches/50.8 cm). . . . . . . . . .
Backglass Wiper Blade Trico (14 inches/35.6 cm). . .
Vehicle Dimensions
Wheelbase 107.0 inches (271.8 cm). . . . . . . . . . . . . .
Length 181.5 inches (460.0 cm). . . . . . . . . . . . . . . . .
Height 67.0 inches (170.2 cm). . . . . . . . . . . . . . . . . . .
Width 67.8 inches (172.2 cm). . . . . . . . . . . . . . . . . . .
Front Tread 57.3 inches (145.4 cm). . . . . . . . . . . . . . .
Rear Tread 55.1 inches (139.9 cm). . . . . . . . . . . . . . .
ProCarManuals.com

Short Trip/City Scheduled Maintenance
yellowblue
7-7
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 ªOwner Checks and Servicesº and ªPeriodic
Maintenance Inspectionsº 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, ball joints, steering
linkage, parking brake cable guides, propshaft splines,
universal joints and brake pedal springs.
+ A good time to check your brakes is during tire
rotation. See ªBrake System Inspectionº under ªPeriodic
Maintenance Inspectionsº in Part C of this schedule.
** Drive axle service (see ªRecommended Fluids and
Lubricantsº 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. 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
heavy
-duty or off-road use.
ProCarManuals.com

Long Trip/Highway Scheduled Maintenance
yellowblue
7-27
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 ªOwner Checks and Servicesº and ªPeriodic
Maintenance Inspectionsº 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, ball joints, steering
linkage, parking brake cable guides, propshaft splines,
universal joints and brake pedal springs.
+ A good time to check your brakes is during tire
rotation. See ªBrake System Inspectionº under ªPeriodic
Maintenance Inspectionsº in Part C of this schedule.
** Drive axle service (see ªRecommended Fluids and
Lubricantsº 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.
ProCarManuals.com

yellowblue
8-7
Trip Interruption Assistance: GMC will reimburse any
reasonable trip interruption expenses (up to $500.00)
when directly associated with warranty disablement. Trip
Interruption service covers expenses such as meals and
overnight lodging if vehicle disablement occurs at least
150 miles (240 km) from your home or rental property.
Please Note: you will be required to obtain prior
approval from GMC Roadside Assistance and pay for
expenses at the time of disablement. Original receipts
should be submitted to GMC Roadside Assistance for
reimbursement. A service representative will provide
assistance when you call.
The Roadside Assistance services listed are available
to retail and retail lease customers operating 1999 GMC
light duty trucks for a period of 3 years/36,000 miles
(60 000 km). All services must be pre
-arranged by
GMC Roadside Assistance.
Over
-the-phone assistance, such as providing the name
of the closest dealer or minor technical advice, etc., is
available to all owner/operators of GMC trucks,
regardless of vehicle or mileage.
Just dial GMC Roadside Assistance at
1
-800-GMC-8782 (1-800-462-8782, Roadside
Assistance prompt) to reach a qualified representative
who can assist you.Your Roadside Assistance representative will ask for the
following information when your call is received:
Vehicle Identification Number (VIN)
Name and home address
Telephone number and location from which you
are calling
Location, license plate number and color of your
GMC truck
Mileage of vehicle and description of problem
Roadside Assistance is available 24 hours a day, 7 days
a week, 365 days a year, including weekends and
holidays. Should you have any questions about roadside
assistance, call the GMC Roadside Assistance Center or
contact your dealer.
Roadside Assistance is not part of or included in the
coverage provided by the New Vehicle Limited Warranty.
GMC reserves the right to make any changes or
discontinue the Roadside Assistance program at any
time without notification.
Canadian Roadside Assistance
Vehicles purchased in Canada have an extensive
Roadside Assistance program accessible from anywhere
in Canada or the United States. Please refer to the
separate brochure provided by the dealer or call
1
-800-268-6800 for emergency services.
ProCarManuals.com

yellowblue
8-9
Courtesy Rental Vehicle
When your vehicle is unavailable due to overnight
warranty repairs, your dealer may arrange to provide
you with a courtesy rental vehicle or reimburse you for a
rental vehicle you obtained, at actual cost, up to a
maximum of $30.00 per day supported by receipts.
This requires that you sign and complete a rental
agreement and meet state, local and rental vehicle
provider requirements. Requirements vary and may
include minimum age requirements, insurance coverage,
credit card, etc. You are responsible for fuel usage
charges and may also be responsible for taxes, levies,
usage fees, excessive mileage or rental usage beyond the
completion of the repair.
Generally it is not possible to provide a like
-vehicle as a
courtesy rental.
Additional Program Information
Courtesy Transportation is available during the
Bumper
-to-Bumper warranty coverage period,
but it is not part of the New Vehicle Limited Warranty.
A separate booklet entitled ªWarranty and Owner
Assistance Informationº furnished with each new
vehicle provides detailed warranty coverage information.Courtesy Transportation is available only at
participating dealerships and all program options, such
as shuttle service, may not be available at every dealer.
Please contact your dealer for specific information about
availability. All Courtesy Transportation arrangements
will be administered by appropriate dealer personnel.
Canadian Vehicles: For warranty repairs during the
Complete Vehicle Coverage period of the General
Motors of Canada New Vehicle Limited Warranty,
alternative transportation may be available under the
Courtesy Transportation Program. Please consult your
dealer for details.
General Motors reserves the right to unilaterally modify,
change or discontinue Courtesy Transportation at any time
and to resolve all questions of claim eligibility pursuant to the
terms and conditions described herein at its sole discretion.
General Motors and participating dealerships reserve the
right to deny a rental vehicle to anyone not possessing a
valid motor vehicle operators license in their name,
anyone who is under the influence of alcohol or drugs, or
anyone whose mental or physical abilities are impaired so
as to be unable to operate a motor vehicle safely.
Warranty Information
Your vehicle comes with a separate warranty booklet
that contains detailed warranty information.
ProCarManuals.com