1999 Chevrolet Astro Owner's Manual - Page 270

yellowblue D After adding fluid, recheck the fluid level as described under "How to Check." How to Check Lubricant D When the correct fluid level is obtained, push the dipstick back in all the way; then flip the handle down to lock the dipstick in place. All-Wheel Drive If you have an all-wheel-drive vehicle, be sure to perform the lubricant checks described in this section. However, they have two additional systems that need lubrication. Transfer Case When to Check Lubricant Refer to the Maintenance Schedule to determine how often to check the lubricant. See "Periodic Maintenance Inspections" 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. 6-24