Chevrolet 1998 Astro Owner's Manual page 286

How to Check Lubricant
Front 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
"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.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See "Recommended Fluids and
Lubricants" 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 "Recommended Fluids and
Lubricants" in the Index.
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