1998 GMC SIERRA suspension

steering, suspension, wheels, tires ana exhaust system
for damage.
Also, check the fuel lines and cooling
system for any leakage. Night driving is more dangerous than
day driving. One
reason is that some drivers are likely to
be impaired -- by
alcohol or
drugs, with night vision problems, or by fatigue.
Your vehicle will require more frequent service due to
off-road use. Refer
to the Maintenance Schedule for
additional information.
Driving at Night
Here are some tips on night driving.
0
0
0
0
0
0
0
Drive defensively.
Don’t drink and drive.
Adjust your inside rearview mirror
to reauce me
glare from headlamps behind you.
Since you can’t see as well,
you may need to
slow down and keep more space between you and
other vehicles.
Slow down, especially on higher speed roads. Your
headlamps can light
up only so much road ahead.
In remote areas, watch for animals.
If you’re tired, pull off
the road in a safe place
and rest.
Night Vision
No one can see as well at night as in the daytime. But as
we get older
these differences increase. A 50-year-old
driver may require at least twice as much light
to see the
same thing at night as a 20-year-old.
4-27
ProCarManuals.com

NOTICE:
Some vehicles may be equipped with RPO VYU
(snow plow prep package). With this option, the
payload your vehicle can carry is reduced when
a
snow plow is installed. Your vehicle can be
damaged if either the front or rear axle ratings,
or the GVW are exceeded.
As a general guideline, with a 650 Ib. (295 kg)
snow plow, the weight of the occupants and cargo
must not exceed
300 lb. (135 kg). However, this
may depend on the vehicle's option content.
Therefore, to help avoid vehicle damage:
0 Make sure the weight on the front and
rear axles does not exceed their respective
axle ratings.
GVW rating.
Total vehicle weight must not exceed the
NOTICE: (Continued)
I NOTICE: (Continued) I
If more cargo or passengers need to be
carried, appropriate counter ballast must
be installed rear of the rear axle and
properly secured.
0 See your dealer for advice and information
about using
a snow plow on your vehicle.
Do not load your vehicle any heavier than the
GVWR, or either the maximum front or rear
GAWR.
If' you do, parts on your vehicle can break,
or it can change the
way your vehicle handles.
These could cause you to lose control.
Also,
overloading can shorten the life of your vehicle.
Using heavier suspension components to get added
durability might not change your weight ratings.
Ask
your dealer to help you load your vehicle the right way.
4-44
ProCarManuals.com

I Short Trip/City Maintenance Schedule -- Gasoline Engines I
The services shown in this schedule up to 100,000 miles
(I 66 000 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
p 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.
7-8
ProCarManuals.com

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

Part C: Periodic
Maintenance Inspections
Listed below are inspections and services which should
be performed at least twice a year (for instance, each
spring and fall).
You should let your dealer’s service
department or other qualified service center
do these
jobs. Make sure any necessary repairs are completed
at once..
Proper procedures to perform these services may be
found in a service manual. See ”Service and Owner
Publications”
in the Index.
Steering and Suspension Inspection
Inspect the front and rear suspension and steering
system for damaged, loose or missing parts, signs of
wear or lack of lubrication. Inspect
the power steering
lines and hoses for proper hook-up, binding, leaks,
cracks, chafing, etc.
Exhaust System Inspection
Inspect the complete exhaust system. Inspect the body
near the exhaust system.
Look for broken, damaged,
missing or out-of-position parts as well as open seams,
holes, loose connections or other conditions which could
cause
a heat build-up in the floor pan or could let
exhaust fumes into the vehicle. See ”Engine Exhaust” in
the Index.
Engine Cooling System Inspection
Inspect the hoses and have them replaced if they are
cracked, swollen or deteriorated. Inspect all pipes,
fittings and clamps; replace as needed. Clean the outside
of the radiator and air conditioning condenser. To help
ensure proper operation, a pressure test of the cooling
system and pressure cap is recommended at least once
a year.
Throttle System Inspection
Inspect the throttle system for interference or binding,
and for damaged or missing parts. Replace parts as
needed. Replace any components that have high effort
or excessive wear.
Do not lubricate accelerator and
cruise control cables.
7-44
ProCarManuals.com

1998 GMC SERVICE PUBLICATIONS ORDERING INFORMATION
The following publications covering the operation and servicing of your vehicle can be purchased by filling o
the Service Publication Order Form in this book and mailing it in with your check, money order,
or credit card information to Helm, Incorporated (address below.)
CURRENT PUBLICATIONS FOR 1998 GMC
SERVICE MANUALS
Service Manuals have the diagnosis and repair information
on engines, transmission, axle, suspension, brakes,
electrical, steering, body, etc.
RETAIL SELL PRICE:
$90.00
TRANSMISSION, TRANSAXLE, TRANSFER CASE
UNIT REPAIR MANUAL
This manual provides information on unit repair service
procedures, adjustments and specifications for the
1998 GM transmissions, transaxles and transfer cases.
RETAIL SELL PRICE:
$40.00
SERVICE BULLETINS
Service Bulletins give technical service information needed
to knowledgeably service General Motors cars and trucks.
Each bulletin contains instructions to assist
in the
diagnosis
and service of your vehicle.
PLEASE COMPLETE THE ORDER FORM SHOWN ON
THE FOLLOWING PAGE AND MAIL TO:
Helm, Incorporated P.O. Box 07130 Detroit, MI 48207
OWNER’S INFORMATION
Owner publications are written directly for Owners and
intended to provide basic operational information about
tl
vehicle. The owner’s manual will include the Maintenanci
Schedule for all models.
In-Portfolio: Includes a Portfolio, Owner’s Manual and
Warranty Booklet.
RETAIL
SELL PRICE: $1 5.00
Without Portfolio: Owner’s Manual only.
RETAIL SELL PRICE:
$1 0.00
CURRENT & PAST MODEL ORDER FORMS
Service Publications are available for current and past
model GM vehicles.
To request an order form, please
specify year and model name of the vehicle.
OR ORDER TOLL FREE: 1-800-782-4356
Monday-Friday 8:OO AM - 6:OO PM Eastern Time
For Credit Card Orders Only
(VISA-Mastercard-Discove
ProCarManuals.com

Tachometer .................................. 2-63
Voltmeter
................................... 2-67
Garage Door Opener
............................ 2-5 1
GAWR ....................................... 4-43
Gear Positions. Automatic Transmission
............. 2- 15
Gear Positions. Manual Transmission .......... 2- I8 . 2- 19
GloveBox .................................... 2-51
Gross Axle Weight Rating ........................ 4-43
Gross Vehicle Weight Rating
...................... 4-43
Guide en Franpis
11
GVWR ....................................... 4-43
.. .................................
Halogen Bulbs ................................ 6-39
Hazard Warning Flashers
.......................... 5-2
Head Restraints ................................. 1-5
Headlamps .................................... 2-41
Bulb Replacement
....................... 6-40. 6.4 I
High/Low Beam Changer ...................... 2-36
On Reminder
................................ 2-42
Wiring
..................................... 6-71
Heating
........................................ 3-5
High-Beam Headlamps
.......................... 2-36
Hill and Mountain Roads
......................... 4-34
Hitches. Trailer
................................. 4-55
Hood
Checking Things Under ......................... 6-9
Release
..................................... 6-10
Horn ......................................... 2-34
Hydraulic Clutch Fluid
...................... 6-25 . 7-46
Hydraulic Clutch System Check
................... 7-41
Hydroplaning
.................................. 4-30
Hearing Ilnpaired
. Customer Assistance .............. 8-4
Highway Hypnosis
.............................. 4-33 Ignition
Positions
..............................
Brakesystem ................................ 7-45
Drive Axle
.................................. 7-45
Engine Cooling System
........................ 7-44
Exhaust
Systems ............................. 7-44
Steering
.................................... 7-44
Suspension
.................................. 7-44
Throttle Linkage
.............................. 7-44
Transfer Case (Four-Wheel Drive)
............... 7-45
Instrument Panel
............................... 2-60
Cleaning
.................................... 6-64
Cluster
..................................... 2-62
FuseBlock
.................................. 6-72
Intensity Control
............................. 2-43
Interior Lamps
................................. 2-43
.................................... J ack. Tire 5-25
Jump Starting
................................... 5-3
Key Lock Cylinders Service
..................... 7-41
Key Release Button
............................. 2-12
Keyless Entry System ............................ 2-6
Keys
.......................................... 2-2
9-5
ProCarManuals.com