Chevrolet 2004 Astro Owner's Manual page 342

90,000 Miles (150 000 km)
Change engine oil and filter (or every 12 months,
whichever occurs first). An Emission Control
Service.
Lubricate chassis components (or every 12 months,
whichever occurs first). (See footnote #).
For Two-Wheel-Drive vehicles only: Clean and
repack the front wheel bearings (or at each
brake relining, whichever occurs first).
Change automatic transmission fluid and filter 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.
6-22
If you do not use your vehicle under any of these
conditions, change the fluid and filter every 50,000 miles
(83 000 km).
Replace fuel filter. An Emission Control Service. (See
footnote †).
Replace engine air cleaner filter. See Engine Air
Cleaner/Filter on page 5-20 for more information.
An Emission Control Service.
Rotate tires. See Tire Inspection and Rotation on
page 5-62 for proper rotation pattern and additional
information. (See footnote +).