GMC 2001 Sierra 1500 Pickup Owner's Manual page 369

5. Perform a hot check at the first opportunity after the
normal operating temperature of 160 _ F (71 _ C) to
200 _ F (93 _ C) is reached.
6. If the fluid level is in the acceptable range, push the
dipstick back in all the way.
Hot Check Procedure
The fluid must be hot to ensure an accurate check.
The fluid level rises as temperature increases.
1. Operate the transmission in DRIVE (D) range until
the normal operating temperature of 160 _ F (71 _ C)
to 200 _ F (93 _ C) is reached.
2. Pull out the dipstick and wipe it with a clean rag or
paper towel.
3. Push it back in all the way, wait three seconds and
then pull it back out again. Repeat the check
procedure to verify the reading.
4. Safe operating level is within the HOT RUN band
on the dipstick. The width of the HOT RUN band
represents approximately 1.06 quart (1.0 liter) of
fluid at normal operating temperature.
5. If the fluid level is not within the HOT RUN band,
add or drain fluid as necessary to bring the fluid
level to within the HOT RUN band.
6. If the fluid level is in the acceptable range, push the
dipstick back in all the way.
Consistency of Readings
Always check the fluid level at least twice using the
procedures described previously. Consistency (repeatable
readings) is important to maintaining proper fluid level.
If inconsistent readings persist, check the transmission
breather to be sure it is clean and unclogged. If readings
are still inconsistent, contact your dealer.
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