GMC Savana 2011 Owner's Manual page 284

10-18 Vehicle Care
How to Check Automatic
Transmission Fluid
Because this operation can be
difficult, it is recommended to
have this check done at the
dealer service department, which
can monitor the transmission
temperature. The transmission fluid
level increases with temperature. To
obtain a highly accurate fluid level
check, the transmission temperature
must be measured.
If it is decided to check the fluid
level, be sure to follow all the
instructions here, or a false reading
on the dipstick may occur.
Notice: Too much or too
little fluid can damage the
transmission. Too much can
mean that some of the fluid could
come out and fall on hot engine
parts or exhaust system parts,
starting a fire. Too little fluid
could cause the transmission
to overheat. Be sure to get an
accurate reading if checking the
transmission fluid.
Wait at least 30 minutes with the
engine Off, before checking the
transmission fluid level if the vehicle
has been driven:
In hot weather, when outside
temperatures are above
32°C (90°F).
The vehicle is heavily loaded.
At high speed for quite a while in
hot weather.
In heavy traffic and hot weather.
While pulling a trailer.
After driving under these conditions,
a hot check can be performed. The
fluid should be Hot, which is 71°C to
93°C (160°F to 200°F).
A cold fluid level check can be
performed after the vehicle has
been sitting for eight hours or more
with the engine off, but this is used
only as a reference. Let the engine
run at idle for five minutes if outside
temperatures is between 15°C to
32°C (60°F to 90°F). Should the
fluid level be low during this cold
check, the fluid must be checked
I n f o r ma t i o n P r o v i d e d b y :
Warm or Hot before adding fluid.
If the outside temperature is colder
than 15°C (60°F) or hotter than
32°C (90°F), a cold check cannot be
performed.
A warm fluid level check can be
performed by driving the vehicle
under lightly loaded conditions and
outside temperatures between 10°C
to 27°C (50°F to 80°F). The vehicle
should be driven for at least 24 km
(15 mi) before performing a warm
check. Checking the fluid Warm
or Hot will give a more accurate
reading of the fluid level than a cold
check.
Because the vehicle is equipped
with a high-efficiency air-to-oil
cooler, the transmission fluid
temperature may not reach the
required Hot fluid level checking
temperature under normal lightly
loaded driving vehicle conditions.