Page 266 of 398

yellowblue
6-12
Engine:
Removal or rendering engine speed governor (if
equipped) inoperative so as to allow engine speed to
exceed manufacturer specifications.
Fan and Drive:
Removal of fan clutch (if equipped) or rendering
clutch inoperative.
Removal of the fan shroud (if equipped).
Air Intake:
Removal of the air cleaner silencer.
Reversing the air cleaner cover.
Exhaust:
Removal of the muffler and/or resonator.
Removal of the exhaust pipes and exhaust
pipe clamps.
Engine Oil (Gasoline Engine)
If your vehicle has a diesel engine, see ªEngine Oil
(Diesel Engine)º in the Diesel Engine Supplement.
Checking Engine Oil
It's a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil must
be warm and the vehicle must be on level ground.
The engine oil dipstick has
a yellow handle and is
located near the center of
the engine compartment.
Turn off the engine and give the oil several minutes to
drain back into the oil pan. If you don't, the oil dipstick
might not show the actual level.
Pull out the dipstick and clean it with a paper towel or
cloth, then push it back in all the way. Remove it again,
keeping the tip down, and check the level.
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6-18
Automatic Transmission Fluid
If your vehicle has a diesel engine, see ªAutomatic
Transmission Fluidº in the Diesel Supplement.
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's GVWR is over 8,600 or
if the vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside temperature
regularly reaches 90F (32C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
If your vehicle's GVWR is not over 8,600 and you
do not use your vehicle under any of these
conditions, change the fluid and filter every
100,000 miles (166 000 km).
See ªScheduled Maintenance Servicesº in the Index.
How to Check
Because this operation can be a little difficult, you
may choose to have this done at the dealership
service department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
NOTICE:
Too much or too little fluid can damage your
transmission. Too much can mean that some of
the fluid could come out and fall on hot engine
parts or exhaust system parts, starting a fire. Be
sure to get an accurate reading if you check your
transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:
When outside temperatures are above 90F (32C).
At high speed for quite a while.
In heavy traffic
-- especially in hot weather.
While pulling a trailer.
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6-23
CAUTION:
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mixture will. Your vehicle's coolant
warning system is set for the proper coolant
mixture. With plain water or the wrong mixture,
your engine could get too hot but you wouldn't
get the overheat warning. Your engine could
catch fire and you or others could be burned. Use
a 50/50 mixture of clean, drinkable water and
DEX
-COOL coolant.
NOTICE:
If you use an improper coolant mixture, your
engine could overheat and be badly damaged.
The repair cost wouldn't be covered by your
warranty. Too much water in the mixture can
freeze and crack the engine, radiator, heater core
and other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
NOTICE:
If you use the proper coolant, you don't have to
add extra inhibitors or additives which claim to
improve the system. These can be harmful.
Page 321 of 398

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6-67 Wheel Nut Torque
MODEL TORQUE
All
140 lb
-ft (190 N´m)
Cooling System Capacity (Approximate)
ENGINE VIN QTY Without Rear Heater QTY With Rear Heater
ªVORTECº 4300 V6 W 11.0 Quarts (10.4 L) 14.0 Quarts (13.2 L)
ªVORTECº 5000 V8 M 17.0 Quarts (16.0 L) 20.0 Quarts (18.9 L)
ªVORTECº 5700 V8 R 17.0 Quarts (16.0 L) 20.0 Quarts (18.9 L)
ªVORTECº 7400 V8 J 23.0 Quarts (21.8 L) 26.0 Quarts (24.6 L)
After refill, the level MUST be checked as outlined under ªEngine Cooling Systemº in Section 5.
Crankcase Capacity (Approximate)
ENGINE VIN Quantity With Filter
ªVORTECº 4300 V6 W 4.5 Quarts (4.3 L)
ªVORTECº 5000 V8 M 5.0 Quarts (4.8 L)
ªVORTECº 5700 V8 R 5.0 Quarts (4.8 L)
ªVORTECº 7400 V8 J 6.0 Quarts (5.6 L)
After refill, the level MUST be rechecked. Add enough engine oil so that the fluid is within the proper operating
range. Variation in oil filter size and oil cooler drainback can cause different fill levels. See ªEngine Oilº in the Index.
*Add one additional quart for RPO 5Z1 and RPO KL5 Models.
Page 329 of 398

Scheduled Maintenance
yellowblue
7-5
Short Trip/City Definition
Follow the Short Trip/City Scheduled Maintenance if
any one of these conditions is true for your vehicle:
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).
Most trips are through dusty areas.
You frequently tow a trailer or use a carrier on top of
your vehicle.
If the vehicle is used for delivery service, police, taxi
or other commercial application.
One of the reasons you should follow this schedule if
you operate your vehicle under any of these conditions
is that these conditions cause engine oil to break
down sooner.
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).
Every 6,000 Miles (10 000 km): Tire Rotation.
Every 15,000 Miles (25 000 km): Engine Air Cleaner
Filter Inspection, if driving in dusty conditions.
Gasoline Engine Only: Noise Shields Inspection
(GVWR above 10,000 lbs. only). Diesel Engine Only:
Shields and Underhood Insulation Inspection. Diesel
Engine Only: Thermostatically Controlled Engine
Cooling Fan Check (or every 12 months, whichever
occurs first). Diesel Engine Only: Air Intake System
Inspection. Front Wheel Bearing Repack (or at each
brake relining, whichever occurs first).
Every 24,000 Miles (40 000 km): Diesel Engine Only:
Fuel Cap Replacement, if driving in dusty conditions.
(Continued)
Page 331 of 398

Scheduled Maintenance
yellowblue
7-7
Long Trip/Highway Definition
Follow this scheduled maintenance only if none of
the conditions from the Short Trip/City Scheduled
Maintenance are 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.
Driving a vehicle with a fully warmed engine under
highway conditions causes engine oil to break
down slower.
Long Trip/Highway Intervals
Every 7,500 Miles (12 500 km): Engine Oil and Filter
Change (or every 12 months, whichever occurs first).
Chassis Lubrication (or every 12 months, whichever
occurs first). Drive Axle Service. Tire Rotation.
Every 15,000 Miles (25 000 km): Gasoline Engine
Only: Noise Shields Inspection (GVWR above
10,000 lbs. only). Diesel Engine Only: Shields and
Underhood Insulation Inspection. Diesel Engine Only:
Thermostatically Controlled Engine Cooling Fan Check
(or every 12 months, whichever occurs first). Diesel
Engine Only: Air Intake System Inspection.
Every 30,000 Miles (50 000 km): Fuel Filter
Replacement. Engine Air Cleaner Filter Replacement.
Front Wheel Bearing Repack (or at each brake
relining, whichever occurs first).
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (vehicles over 8600 GVWR
or driven under severe conditions or equipped with
diesel engine).
(Continued)
Page 333 of 398

Short Trip/City Scheduled Maintenance
yellowblue
7-9
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 ªOwner Checks and Servicesº and ªPeriodic
Maintenance Inspectionsº 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 and rear driveline center splines.
+ A good time to check your brakes is during tire
rotation. See ªBrake System Inspectionº under
ªPeriodic Maintenance Inspectionsº in Part C
of this schedule.
** Drive axle service (see ªRecommended Fluids and
Lubricantsº in the Index for proper lubricant to use):
Check fluid level and add fluid as needed. If driving
in dusty areas or when towing a trailer, drain fluid
and refill every 15,000 miles (25 000 km).
If your vehicle has a locking differential, drain fluid
and refill at first engine oil change.
More frequent lubrication may be required for
heavy
-duty use.
Page 334 of 398

Short Trip/City Scheduled Maintenance
yellowblue
7-10
3,000 Miles (5 000 km)
Change engine oil and filter (or every 3 months, whichever occurs first).
An Emission Control Service.
Lubricate chassis components (or every 3 months, whichever occurs first).
(See footnote #.)
Check axle fluid level and add fluid as needed. (See footnote **.)
6,000 Miles (10 000 km)
Change engine oil and filter (or every 3 months, whichever occurs first).
An Emission Control Service.
Lubricate chassis components (or every 3 months, whichever occurs first).
(See footnote #.)
Check axle fluid level and add fluid as needed. (See footnote **.)
Rotate tires. See ªTire Inspection and Rotationº in the Index for proper
rotation pattern and additional information. (See footnote +.)
9,000 Miles (15 000 km)
Change engine oil and filter (or every 3 months, whichever occurs first).
An Emission Control Service.
Lubricate chassis components (or every 3 months, whichever occurs first).
(See footnote #.)
Check axle fluid level and add fluid as needed. (See footnote **.)
ACTUAL
SERVICED BY:MILEAGE
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ACTUAL
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ACTUAL
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