1997 Chevrolet Astro Owner's Manual - Page 280

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. 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. If the level is below the bottom of the fillerplug hole, you'll need to add some lubricant. Add enough lubricant to raise the level to bottom of the fillerplug hole. the What to Use Refer to theMaintenance Schedule to determine what kind of lubricant to use. See "Recommended Fluids and Lubricants" in the Index. What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See "Recommended Fluids and Lubricants" in the Index. 6-24