GMC 1999 Envoy, Owner'S Manual

Page: 342 / 384

Long Trip/Highway Scheduled Maintenance
yellow blue
7-30
30,000 Miles (50 000 km) (Continued)
j Lubricate chassis components (or every 12 months, whichever occurs first).
(See footnote #.)
j Check rear/front axle fluid level and add fluid as needed. Check constant
velocity joints and axle seals for leaking. (See footnote **.)
j 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.
If you do not use your vehicle under any of these conditions, change the fluid
and filter every 50,000 miles (83 000 km).
j Rotate tires. See “Tire Inspection and Rotation” in the Index for proper
rotation pattern and additional information. (See fo.)
j Replace fuel filter.
An Emission Control Service. (See footnote
[.)
j Replace air cleaner filter.
An Emission Control Service.