GMC 2005 T-Series Owner's Manual page 259

(17) = With the engine off and below normal operating
temperature, check to see that the thermostatically
controlled engine cooling fan can be rotated by hand on
viscous-operated drives. Replace as needed.
(18) = Check shields and underhood insulation for
damage or looseness. Adjust or replace as needed.
(19) = Wheel bearing service:
•
Grease type – Clean, inspect and lubricate with the
proper wheel bearing grease at designated intervals
or when hubs are removed. See Part C:
Recommended Fluids and Lubricants on page 6-28.
•
Oil-filled type – Some wheel bearings are lubricated
by rear axle lubricant. When you have oil-filled
hubs, use lubricant identical to that used in your rear
axle. Lubricant change intervals are the same for
front and rear axles. However, you must maintain oil
level at the OIL LEVEL mark between change
intervals. See Part C: Recommended Fluids and
Lubricants on page 6-28.
(20) = Check the air intake system installation to see
that gaskets are seated properly and all hose
connections, fasteners and other components are tight.
Tighten connections and fasteners or replace parts
as required.
(21) = Check the fuel tank, fuel cap and fuel lines for
damage which could cause leakage. Inspect fuel cap for
correct sealing ability and any indications of damage.
Check fuel cap gasket for even filler neck imprint.
Replace parts as needed.
(22) = Inspect Electronic Vacuum Regulator
Valve (EVRV) filter for excessive contamination or
plugging. If needed, clean filter with solution of soap
and water, let dry and install.
(23) = Drain, flush and refill cooling system. See Part C:
Recommended Fluids and Lubricants on page 6-28
for what to use. Inspect hoses. Clean radiator,
condenser, pressure cap and neck. Pressure test
cooling system and pressure cap.
(24) = Rear axle service: Change the lubricant. See
Part C: Recommended Fluids and Lubricants on
page 6-28.
(25) = Front axle service: Re-pack upper kingpin roller
bearing.
6-21