GMC 2002 Sierra - Manual (Page 395)

6-28
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.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission fluid to use. See “Recommended
Fluids and Lubricants” in the Index.
Add fluid only after checking the transmission fluid
while it is hot. (A cold check is used only as a
reference.) If the fluid level is low, add only enough of
the proper fluid to bring the level up to the HOT area for
a hot check. It doesn’t take much fluid, generally less
than one pint (0.5 L). Don’t overfill.