Buick Enclave 2008 Owner's Manual page 322

Then, without shutting off the engine, follow these steps:
See Engine Compartment Overview on page 5-12 for
more information on location.
1. Remove the dipstick and wipe it with a clean rag or
paper towel.
2. Reinstall back in all the way, wait three seconds
and then pull it back out again.
The transmission fluid
dipstick cap has this
symbol on it, and is
located near the front
of the engine compartment.
3. Check both sides of the dipstick, and read the
lower level. The fluid level must be in the
crosshatched area.
4. If the fluid level is in the acceptable range,
twist & lock dipstick cap in place.
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