Page 356 of 452

(A) Light Truck (LT-Metric) Tire:The United States
version of a metric tire sizing system. The letter ªLTº as
the ®rst two characters in the tire size means a light
truck tire engineered to standards set by the U. S. Tire
and Rim Association.
(B) Tire Width:The three-digit number indicates the
tire section width in millimeters from sidewall to sidewall.
(C) Aspect Ratio:A two-digit number that indicates
the tire height-to-width measurements. For example, if
the tire size aspect ratio is ª75,º as shown in item ªCº of
the illustration, it would mean that the tire's sidewall is
75% as high as it is wide.(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire. The
letter ªRº means radial ply construction; the letter ªDº
means diagonal or bias ply construction; and the
letter ªBº means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:The service description
indicates the load range and speed rating of a tire.
The load index can range from 1 to 279. Speed ratings
range from ªAº to ªZº. The light truck tire size example
above shows dual or single tire con®gurations.Tire Terminology and De®nitions
Air Pressure:The amount of air inside the tire pressing
outward on each square inch of the tire. Air pressure
is expressed in pounds per square inch (psi) or
kilopascal (kPa).
Accessory Weight:This means the combined weight
of optional accessories. Some examples of optional
accessories are, automatic transmission, power steering,
power brakes, power windows, power seats, and air
conditioning.
Aspect Ratio:The relationship of a tire's height to
its width.
Belt:A rubber coated layer of cords that is located
between the plies and the tread. Cords may be made
from steel or other reinforcing materials. Light Truck (LT-Metric) Tire
5-64
Page 404 of 452
Fuses Usage
TBC BATTTruck Body Controller
Battery Feed
SUNROOF Sunroof
SEO B2 Off-Road Lamps
4WSVent Solenoid
Canister/Quadrasteer
Module Power
RR HVAC Not Used
AUX PWRAuxiliary Power
Outlet Ð Console
IGN 1 Ignition Relay
PCM 1 Powertrain Control Module
ETC/ECMElectronic Throttle Control,
Electronic Brake Controller
IGN EInstrument Panel Cluster,
Air Conditioning Relay,
Turn Signal/Hazard Switch,
Starter Relay
RTD Ride Control
TRL B/U Backup Lamps Trailer WiringFuses Usage
PCM BPowertrain Control Module,
Fuel Pump
F/PMP Fuel Pump (Relay)
B/U LPBack-up Lamps, Automatic
Transmission Shift Lock
Control System
RR DEFOG Rear Window Defogger
HDLP-HI Headlamp High Beam Relay
PRIME Not Used
02B Oxygen Sensors
SIRSupplemental In¯atable
Restraint System
FRT PARKFront Parking Lamps,
Sidemarker Lamps
DRLDaytime Running
Lamps (Relay)
SEO IGN Rear Defog Relay
TBC IGN1 Truck Body Controller Ignition
HI HDLP - LT High Beam Headlamp - Left
5-112
Page 412 of 452
Additional Required Services
The following services should be performed at the ®rst maintenance service (IorII) after the indicated miles
(kilometers) shown for each item.
Additional Required Services
Service25,000
(41 500)50,000
(83 000)75,000
(125 000)100,000
(166 000)125,000
(207 500)150,000
(240 000)
Inspect fuel system for damage
or leaks.······
Inspect exhaust system for loose or
damaged components.······
Vehicles without a ®lter restriction
indicator: Replace engine air cleaner
®lter. See
Engine Air Cleaner/Filter on
page 5-16.An Emission Control
Service.······
Change automatic transmission ¯uid
and ®lter (severe service).
See footnote (h).···
Change automatic transmission ¯uid
and ®lter (normal service).·
Inspect evaporative control system.
An Emission Control Service. See
footnotes ² and (g).···
6-6
Page 415 of 452

(g)Add ¯uid as needed. A ¯uid loss could indicate a
problem; repair as needed. Check vent hose at transfer
case for kinks and proper installation.
(h)Change automatic transmission ¯uid and ®lter if the
vehicle is mainly driven under one or more of these
conditions:
þIn heavy city traffic where the outside temperature
regularly reaches 90ÉF (32ÉC) or higher.
þIn hilly or mountainous terrain.
þWhen doing frequent trailer towing.
þUses such as found in taxi, police or delivery
service.
(i)Drain, ¯ush and re®ll cooling system. See Engine
Coolant on page 5-21for what to use. Inspect hoses.
Clean radiator, condenser, pressure cap and ®ller neck.
Pressure test the cooling system and pressure cap.
(j)
A ¯uid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the ¯uid level checked. Add ¯uid if needed.
(k)Inspect system. Check all fuel and vapor lines and
hoses for proper hook-up, routing and condition.
Check that the purge valve works properly (if equipped).
Replace as needed.
Owner Checks and Services
These owner checks and services should be performed
at the intervals speci®ed to help ensure the safety,
dependability and emission control performance of your
vehicle. Your GM Goodwrench dealer can assist you
with these checks and services.
Be sure any necessary repairs are completed at once.
Whenever any ¯uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
in
Recommended Fluids and Lubricants on page 6-13.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel ®ll.
Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-11for further
details.
Notice:It is important to check your oil regularly
and keep it at the proper level. Failure to keep your
engine oil at the proper level can cause damage
to your engine not covered by your warranty.
6-9
Page 417 of 452

Automatic Transmission Shift Lock
Control System Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle. It should be parked on a level
surface.
2. Firmly apply the parking brake. See
Parking Brake
on page 2-25if necessary.
Be ready to apply the regular brake immediately if
the vehicle begins to move.3. With the engine off, turn the key to the RUN
position, but do not start the engine. Without
applying the regular brake, try to move the shift
lever out of PARK (P) with normal effort. If the shift
lever moves out of PARK (P), contact your GM
Goodwrench dealer for service.
Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn
the ignition key to LOCK in each shift lever position.
·The key should turn to LOCK only when the
shift lever is in PARK (P).
·The key should come out only in LOCK.
Contact your GM Goodwrench dealer if service is
required.
6-11
Page 418 of 452

Parking Brake and Automatic
Transmission Park (P) Mechanism Check
{CAUTION:
When you are doing this check, your vehicle
could begin to move. You or others could be
injured and property could be damaged. Make
sure there is room in front of your vehicle in
case it begins to roll. Be ready to apply the
regular brake at once should the vehicle begin
to move.Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular brake, set the
parking brake.
·To check the parking brake's holding ability: With
the engine running and transmission in
NEUTRAL (N), slowly remove foot pressure from
the regular brake pedal. Do this until the vehicle is
held by the parking brake only.
·To check the PARK (P) mechanism's holding ability:
With the engine running, shift to PARK (P). Then
release the parking brake followed by the regular
brake.
Contact your GM Goodwrench dealer if service is
required.
Underbody Flushing Service
At least every spring, use plain water to ¯ush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
6-12
Page 419 of 452

Recommended Fluids and
Lubricants
Fluids and lubricants identi®ed below by name, part
number or speci®cation may be obtained from your
dealer.
Usage Fluid/Lubricant
Engine OilEngine oil which meets GM
Standard GM6094M and displays
the American Petroleum Institute
Certi®ed for Gasoline Engines
starburst symbol. To determine the
proper viscosity for your vehicle's
engine, see
Engine Oil on
page 5-11.
Engine Coolant50/50 mixture of clean, drinkable
water and use only
DEX-COOL
žCoolant. SeeEngine
Coolant on page 5-21.
Hydraulic Brake
SystemDelco Supreme 11 Brake Fluid or
equivalent DOT-3 brake ¯uid.
Windshield
Washer SolventGM Optikleen
žWasher Solvent.
Usage Fluid/Lubricant
Power Steering
SystemGM Power Steering Fluid
(GM Part No. U.S. 89021184, in
Canada 89021186).
Automatic
TransmissionDEXRON
ž-III Automatic
Transmission Fluid.
Key Lock
CylindersMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241, in
Canada 10953474).
Floor Shift
LinkageLubriplate Lubricant Aerosol
(GM Part No. U.S. 12346293, in
Canada 992723) or lubricant
meeting requirements of NLGI #2
Category LB or GC-LB.
Chassis
LubricationChassis Lubricant
(GM Part No. U.S. 12377985, in
Canada 88901242) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
Front AxleSAE 75W-90 Synthetic
Axle Lubricant
(GM Part No. U.S. 12378261, in
Canada 10953455) meeting GM
Speci®cation 9986115.
6-13
Page 420 of 452

Usage Fluid/Lubricant
Rear Axle
(Steerable)Synthetic Axle Lubricant; use only
GM Part No. 12378557
(in Canada 88901362).
Do not add friction modi®er.
Transfer CaseDEXRON
ž-III Automatic
Transmission Fluid.
Rear Driveline
Center SplineChassis Lubricant
(GM Part No. U.S. 12377985, in
Canada 88901242) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
Front Axle
Propshaft
SplineSpline Lubricant, Special Lubricant
(GM Part No. U.S. 12345879, in
Canada 10953511) or lubricant
meeting requirements of
GM 9985830.
Hood HingesMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241, in
Canada 10953474).
Usage Fluid/Lubricant
Body Door
Hinge Pins,
Tailgate Hinge
and Linkage,
Folding Seats
and Fuel Door
HingeMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241, in
Canada 10953474).
Tailgate Handle
Pivot Points,
Hinges, Latch
Bolt and
LinkageMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241, in
Canada 10953474).
Weatherstrip
ConditioningDielectric Silicone Grease
(GM Part No. U.S. 12345579, in
Canada 992887).
Weatherstrip
SqueaksSynthetic Grease
with Te¯on, Superlube
(GM Part No. U.S. 12371287, in
Canada 10953437).
6-14