(f)Lubricate all key lock cylinders, body door hinges,
hood latch assembly, secondary latch, pivots, spring
anchor, release pawl, tailgate hinges, tailgate linkage,
tailgate handle pivot points, latch bolt, fuel door hinge,
locks, and folding seat hardware. More frequent
lubrication may be required when exposed to a corrosive
environment. Applying silicone grease on weatherstrips
with a clean cloth will make them last longer, seal better,
and not stick or squeak.
(g)Check vent hose at transfer case for kinks and proper
installation. Check to be sure vent hose is unobstructed,
clear, and free of debris. During any maintenance, if a
power washer is used to clean mud and dirt from the
underbody, care should be taken to not directly spray the
transfer case output seals. High pressure water can
overcome the seals and contaminate the transfer case
fluid. Contaminated fluid will decrease the life of the
transfer case and should be replaced.
(h)Change automatic transmission fluid and filter if
the vehicle Gross Vehicle Weight Rating (GVWR) is over
8600 lbs or 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.(i)Drain, flush, and refill cooling system. This service
can be complex; you should have your dealer/retailer
perform this service. See Engine Coolant on page 5-29
for what to use. Inspect hoses. Clean radiator,
condenser, pressure cap, and filler neck. Pressure test
the cooling system and pressure cap.
(j)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the fluid level checked. Add fluid 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, if the vehicle has one, works
properly. Replace as needed.
(l)Extreme Duty Service: Change transfer case fluid if
the vehicle is mainly driven off-road in four-wheel
drive. Vehicles used for farming, mining, forestry,
Department of Natural Resources (DNR), and snow
plowing occupations meet this definition.
(m)Severe Duty Service: Change transfer case fluid if
the vehicle is mainly driven under one or more of
these conditions:
Frequent trailer towing.
Taxi, police, or delivery service.
6-10
Recommended Fluids and
Lubricants
This maintenance section applies to vehicles with a
gasoline engine. If your vehicle has a diesel engine, see
the maintenance schedule section in the DURAMAX
®
Diesel manual.
Fluids and lubricants identi ed below by name, part
number, or speci cation can be obtained from your
dealer/retailer.
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, seeEngine Oil on page 5-15.
Engine Coolant50/50 mixture of clean, drinkable
water and use only DEX-COOL
®
coolant. SeeEngine Coolant on
page 5-29.
Hydraulic Brake
SystemDelco
®Supreme 11 Brake Fluid or
equivalent DOT-3 brake uid.
Windshield
WasherOptikleen
®Washer Solvent.
Usage Fluid/Lubricant
Power Steering
SystemGM Power Steering Fluid
(GM Part No. U.S. 89021184,
in Canada 89021186).
Automatic
TransmissionDEXRON
®-VI 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 Axle
(1500 Series) -
Four-Wheel
DriveSAE 80W-90 Axle Lubricant
(GM Part No. U.S. 89021671,
in Canada 89021672).
Front Axle
(1500 HD,
1500 AWD,
2500,
2500 HD, and
3500 Series)SAE 75W-90
Synthetic Axle Lubricant
(GM Part No. U.S. 89021677,
in Canada 89021678) meeting
GM Speci cation 9986115.
6-15