Chevrolet 2007 TrailBlazer Owner's Manua page 379

Parking on Hills
CAUTION:
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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.
But if you ever have to park your rig on a hill,
here's how to do it:
1. Apply your regular brakes, but don't shift into
PARK (P) yet. When parking uphill, turn your
wheels away from the curb. When parking
downhill, turn your wheels into the curb.
2. Have someone place chocks behind 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).
5. Release the regular brakes.
CAUTION:
{
It can be dangerous to get out of your
vehicle if the shift lever is not fully in
PARK (P) with the parking brake firmly
set. Your vehicle can roll.
If you have left the engine running, the
vehicle can move suddenly. You or others
could be injured. To be sure your vehicle
will not move, even when you are on fairly
level ground, use the steps that follow.
Always put the shift lever fully in PARK (P)
with the parking brake firmly set.
If the transfer case on four-wheel drive
vehicles is in NEUTRAL, your vehicle will
be free to roll, even if your shift lever is in
PARK (P). So, be sure the transfer case is
in a drive gear — not in NEUTRAL.
See Four-Wheel Drive on page 121.
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