GMC 2004 Sonoma Owner's Manual page 265

Checking the Automatic Transmission
Fluid Level
Prepare your vehicle as follows:
•
Park your vehicle on a level place. Keep the engine
running.
•
With the parking brake applied, place the shift lever
in PARK (P).
•
With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever in PARK (P).
•
Let the engine run at idle for three minutes or more.
Then, without shutting off the engine, follow
these steps:
The transmission dipstick is located near the center of
the engine compartment. See Engine Compartment
Overview on page 5-12 for more information on location.
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. To get an accurate reading, when checking the fluid
level, keep the tip of the dipstick down to avoid the
fluid traveling up the dipstick.
The transmission dipstick
handle has this symbol
on it.
5-21