Chevrolet 2007 Cobalt Owner's Manual page 268

When towing under severe conditions such as hot
ambient temperatures or steep grades, your
vehicle may experience more transaxle shifting.
A COOLING MODE ON message may also appear
in the DIC. This alerts the driver that the shifting
mode is in progress and is aiding engine cooling.
See DIC Warnings and Messages on page 180
for more information.
Parking on Hills
CAUTION:
{
You really should not park your vehicle,
with a trailer attached, on a hill.
If something goes wrong, your rig could
start to move. People can be injured, and
both your vehicle and the trailer can be
damaged.
268
But if you ever have to park your rig on a hill,
here is how to do it:
1. Apply your regular brakes, but do not shift into
PARK (P) for an automatic transaxle, or into
gear for a manual transaxle. When parking
uphill, turn your wheels away from the
curb. When parking downhill, turn your wheels
into the curb.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release
the regular brakes until the chocks absorb
the load.
4. Reapply the regular brakes. Then apply your
parking brake, and then shift into PARK (P) for
an automatic transaxle or REVERSE (R) for a
manual transaxle.
5. Release the regular brakes.