GMC 1996 Sierra Owner's Manual page 271

How to Add Fluid
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.
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
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 a
pint (-0.5 L). Don't overjill. We recommend you use only
fluid labeled DEXRON@-111, because fluid with that
label is made especially for your automatic transmission.
Damage caused by fluid other than DEXRON-I11 is not
covered by your new vehicle warranty.
0
After adding fluid, recheck the fluid level as
described under "How to Check."
0
When the correct fluid level is obtained, push the
dipstick back in all the way; then flip the handle
down to lock the dipstick in place.
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