Chevrolet 2011 Express 1500 Cargo Owner's Manual page 287

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
determine what kind of transmission
fluid to use.
A. WARM Range
B. HOT Range
Using a funnel, add fluid down the
transmission dipstick tube only after
checking the transmission fluid
while it is warm or 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 middle of the WARM (A) or
HOT (B) range depending on the
ambient temperature and prior
to
driving conditions. Refer to How to
Check Automatic Transmission
Fluid , earlier in this section for
instructions on driving to achieve
warm or hot transmission fluid.
It does not take much fluid,
generally less than 0.5 L (1 pt).
Do not overfill.
After adding fluid, recheck the
fluid level as described under
How to Check Automatic
Transmission Fluid, earlier
in this section.
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.