Chevrolet 1998 Tracker Owner's Manual page 259

Rear Axle What to Use
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
"Periodic Maintenance Inspections" and "Scheduled
Maintenance Services" in the Index.
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.
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See "Recommended Fluids
and Lubricants" in the Index.
Four-wheel Drive
Most lubricant checks in this section also apply to
four-wheel-drive vehicles. However, they have two
additional systems that need lubrication.
Transfer Case
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 "Scheduled Maintenance Services" in the Index.
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