Page 271 of 410

Engine Oil Additives
Don't add anything to your oil. YOLK GM dealer is ready
to advise
if you think something should be added.
When to Change Engine Oil
If any one of these is true for you. LIS~ the short trip/city
. maintenxm schedule:
Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.
Most trips include extensive idling (such as frequent
driving
in stop-and-go traffic).
0 You operate your vehicle in dusty areas or
off-road frequently.
YOLI frequently tow a trailer or use a carrier on top of
your vehicle.
The vehicle is used for delivery service, police, taxi
or other commercial application. Driving under
these conditions causes engine oil to
break
down sooner. If any one of these is true for your
vehicle. then you need to change your
oil and filter
every
3.000 miles (5 000 km) or 3 months -- whichever
occurs first.
Remote Oil Filter (Four-wheel Drive)
The ;1ccess door for the remote oil filter is in the steering
linkage shicld
assembly located under the radiator
support. Twist the
screw to unlock or lock the door.
Make sure
if you open the door, it is securely closed
when you are finished.
6-12
Page 273 of 410

Automatic Transmission Fluid
Operating the engine with the air cleaner 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
off.
I NOTICE:
If the air cleaner 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
in place when you're driving.
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 50.000 miles
(83 000 km) if the vehicle is mainly driven under one or
more of these conditions:
In heavy city traffic where the outside temperature
regularly reaches
90°F (32°C) 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, the fluid and filter do not require changing.
See "Scheduled Maintenance Services"
in the Index.
6-14
Page 322 of 410

Capacities and Specifications
Engine Description ............ “VORTEC” 4300
Type .................................... V6
VINCode ................................. W
Firing Order ...................... 1-6-5-4-3-2
Horsepower
................... 190 at 4,400 rpm
Thermostat Specification ........... I95 OF (9 I “C)
Spark Plug Gap .......... 0.045 inches (0. I 14 cm)
Wheels and Tires
Wheel Nut Torque ............ 95 lb-ft ( 130 N-m)
Tire Pressure ...... See the Certification/Tire label.
See ”Loading Your
Vehicle”
in the Index.
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.
Thermostat
......................... 12551472
Oil Filter.. ............................. PF52
Air Cleaner Filter
...................... A 1 163C
PCV Valve
.......................... CV746C
Automatic Transmission Filter
Kit ...... 24200796
Spark Plugs
........................... 4 1-932
Fuel Filter. ............................ GF481
Front Windshield
Wiper Blade
.......... Trico (20 inchedS0.8 cm)
Backglass Wiper Blade
... Trico (14 inched35.6 cm)
6-63
Page 328 of 410

Maintenance Schedule
Short TripKity Definition
Follow the Short Trip/City Maintenance Schedule if any
one
of' these conditions is true for your
ehick:
0 Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.
driving
in stop-and-go traffic).
off-road frequently.
your vehicle.
or other comnwcial application.
0 Most trips include extensive idling (such as frequent
0 You operate your vehicle in dusty areas or
0 You I-'recluently tow a trailer or use a carrier on top of
0 If the vehicle is used for delivery service, police, taxi
OII~? of'the 1-ec1,son.s !*OLL .sho~rl~l,fi,ll~~t~~ this .sc*Iwdulc~ if you
optute !mrr \vl?ic*le L~OI- elq* of' thesc c-oditiorzs is tlwt
those cwclitior1.v
(YILIS~ e~lgiw oil to h~wk lloc
SOOIIOK
Short Trip/City Intervals
Every 3,000 Miles (5 000 km): Engine Oil and Filter
Change
(or 3 months, whichever occurs first). Chassis
Lubrication (or
3 months. whichever occurs first). Drive
Axle Service (or 3 months, whichever occurs first).
Short TripKity Intervals
Every 6,000 Miles (10 000 km): Tire Rotation.
Every 15,000 Miles (25 000 km): Air Cleaner Filter
Inspection.
if' driving in dusty conditions. Front
Wheel Bearing Repack (2WD only) (or at each brake
relining, whichever occurs
first).
Every 30,000 Miles (50 000 km): Air Cleaner Filter
Replacement. Fuel Filter Replacement.
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (severe conditions only).
Every 60,000 Miles (100 000 km): Engine
Accessory Drive Belt Inspection. Fuel Tank, Cap
and Lines Inspection.
Every 100,000 Miles (166 000 km): Spark Plug Wire
Inspection. Spark Plug Replacement. Positive
Crankcase Ventilation (PCV
j Valve Inspection.
Every 150,000 Miles (240 000 km): Cooling System
Service (or every
60 months. whichever occ~lrs first).
Thc>,vt> if?ter~ul.s o~l~- .swwncrri:o 1uc1intemtlce ser\!ic:t>s.
He ,s11t-~3 to folloct- the c-omplote mrlirztencrnc'cJ .sc*he,dult?
on tl~~~.~~)ll~)~~,i~l~~ pclgr.s.
7-5
Page 329 of 410

Maintenance Schedule
I Long Trip/Hiahway Definition
Follow this maintenance schedule only if none of the
conditions from the Short Trip/City Maintenance
Schedule
is true. Do not use this schedule if the vehicle
is used
for trailer towing, driven in a dusty area or used
off paved roads. Use the Short Trip/City schedule for
these conditions.
Lone TridHiehwav Intervals
Every 7,500 Miles (12 500 km): Engine Oil and Filter
Change (or every
12 months, whichever C)CCLI~S first).
Chassis Lubrication (or every
I2 months, whichever
occ~~rs first). Drive Axle Service. Tire Rotation.
Every 30,000 Miles (50 000 km): Fuel Filter
Replacement.
Air Cleaner Filter Replacement. Front
Wheel Bearing Repack (2WD only) (or at each brake
relining, whichever occurs first).
Transmission Service (severe conditions only).
Drive Belt Inspection. Fuel
Tank, Cap and
Lines Inspection.
Inspection. Spark Plug Replacement. Positive
Crankcase Ventilation (PCV) Valve Inspection.
Every 150,000 Miles (240 000 km): Cooling System
Service
(or every 60 months. whichever occurs first).
Every 50,000 NIiles (83 000 km): Automatic
Every 60,000 Miles (100 000 km): Engine Accessory
Every 100,000 Miles (166 000 km): Spark Plug Wire
7-6
Page 331 of 410
Short Trip/City Maintenance Schedule
3,000 Miles (5 000 km)
Change engine oil and filter (or every
3 months, whichever occurs first).
0 Lubricate chassis components (or every
3 months, whichever occurs first).
(See footnote
#.)
0 Check readfront axle fluid level and add
fluid
as needed. Check constant velocity
joints and axle seals for leaking.
(See footnote
?)
DATE SERVICED BY: ACTUAL MILEAGE
6,000 Miles (10 000 km)
CI Change engine oil and filter (or every
3 months, whichever occurs first).
A17 Emissiou Colltr-ol Sar.\.ic.e.
CI Lubricate chassis components (or every
3 months, whichever occurs first).
(See footnote
#.)
0 Check readfront axle fluid level and add fluid
as need.ed. Check constant velocityjoints and
axle seals
for leaking. (See footnote T)
0 Rotate tires. See “Tire Inspection and
Rotation”
in the Index for proper rotation
pattern and additional information.
(See footnote
+.)
I DATE I ACTUAL MILEAGE ISERVICED BY I
7-8
Page 332 of 410
I Short Trip/City Maintenance Schedule I
9,000 Miles (15 000 km)
0 Change engine oil and filter (or every
3 months, whichever occurs first).
AH Emissio/1 Control Sc>t-\!ir-o.
0 Lubricate chassis components (or every
3 months, whichever occurs first).
(See footnote
#.)
0 Check readfront axle fluid level and add
fluid as needed. Check constant velocity
joints and axle seals for leaking.
(See footnote
'Y)
DATE SERVICED BY: ACTUAL IC.III,EAGE
12,000 Miles (20 000 km)
0 Change engine oil and filter (or every
3 months, whichever occurs first).
At! Emissio/l Control ScJl-\'ic.c.
0 Lubricate chassis components (or every
3 months. whichever occurs first).
(See footnote
#.)
0 Check rear/front axle fluid level and add
fluid as needed. Check constant velocity
.joints and axle seals for leaking.
(See footnote
'!?)
0 Rotate tires. See "Tire Inspection and
Rotation"
in the Index for proper rotation
pattern and additional information.
(See footnote
+.)
7-9
Page 333 of 410
I Short TripKity Maintenance Schedule I
15,000 Miles (25 000 km)
0 Change engine oil and filter (or every
3 months, whichever occurs first).
An Emission Control Service.
0 Lubricate chassis components (or every
3 months, whichever occurs first).
(See footnote
#.)
0 Inspect air cleaner filter if you are
driving in dusty conditions. Replace filter
if necessary.
An Emission Control Service. (See footnote?.)
0 Check readfront axle fluid level and add
fluid as needed. Check constant velocity
joints and axle seals for lealung.
(See footnote
**.)
0 For Two-Wheel-Drive vehicles only: Clean and repack the front wheel bearings (or at
each brake relining, whichever occurs first).
DATE ACTUAL MILEAGE SERVICED BY
7-10