Page 287 of 412

6-18
CAUTION:
Operating the engine with the air cleaner/filter
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/filter off.
NOTICE:
If the air cleaner/filter 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/filter in place when
you're driving.
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.
Page 291 of 412

6-22
Rear Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change it.
See ªScheduled Maintenance Servicesº in the Index.
How to Check Lubricant
If the level is below the
bottom of the filler plug
hole, you'll need to add
some lubricant. Add enough
lubricant to raise the level
to the bottom of the filler
plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See ªRecommended Fluids and
Lubricantsº in the Index.
Engine Coolant
The cooling system in your vehicle is filled with
DEX
-COOL engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs first, if you add only
DEX
-COOL extended life coolant.
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
with engine overheating, see ªEngine Overheatingº in
the Index.
A 50/50 mixture of clean, drinkable water and
DEX
-COOL coolant will:
Give freezing protection down to
-34F (-37C).
Give boiling protection up to 265F (129C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
Page 338 of 412
6-69 Crankcase Capacity
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 8100 V8 G 6.5 quarts (6.15 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.
Fuel Tank Capacity
TYPE QUANTITY MODEL TYPE
Standard Tank 31.0 U.S. gallons (117.3 L) Passenger and Cargo
Standard Tank 35.0 U.S. gallons (132.5 L) Cab and Chassis
Optional Tank* 55.0 U.S. gallons (208.1 L) Cab and Chassis
*159 inch wheelbase or 177 inch wheelbase
Page 348 of 412

Short Trip/City Scheduled Maintenance
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 349 of 412

Short Trip/City Scheduled Maintenance
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
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE
Page 350 of 412

Short Trip/City Scheduled Maintenance
7-11
12,000 Miles (20 000 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 +.)
15,000 Miles (25 000 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 #.)
Diesel Engine Only: Inspect engine air cleaner filter if you are driving in dusty
conditions. Replace filter if necessary.
An Emission Control Service. (See footnote .)
Gasoline Engine Only: See ªEngine Air Cleaner Filter Restriction Indicator
Checkº in the Index.
Check axle fluid level and add fluid as needed. (See footnote **.)
(Continued)
ACTUAL
SERVICED BY:MILEAGE
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE
Page 352 of 412
Short Trip/City Scheduled Maintenance
7-13
18,000 Miles (30 000 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 +.)
21,000 Miles (35 000 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
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE
Page 353 of 412
Short Trip/City Scheduled Maintenance
7-14
24,000 Miles (40 000 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 +.)
Diesel Engine Only: Replace fuel filler cap if driving in dusty conditions.
An Emission Control Service.
27,000 Miles (45 000 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
DATE
ACTUAL
SERVICED BY:MILEAGE
DATE