Chevrolet 1997 Astro Owner's Manual page 278

Then, without shutting ofT the engine, follow these steps:
1. Flip the handle up and then pull out the dipstick and
wipe it with a clean rag or paper towel.
2. Push it
back in all the way, wait three seconds and
then pull it back out again.
3. Check both sides of the dipstick, and read the lower
level. The fluid level must be in the COLD area for a
cold check or in the HOT area or cross-hatched area
for a hot check.
4. If the fluid level is in the acceptable range, push the
dipstick back in all the way; then flip the handle
down to lock the dipstick in place.
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