Chevrolet 2004 Blazer Owner's Manual page 273

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, or into gear for a manual
transmission. Then turn your wheels into the curb if
facing downhill or into traffic if facing uphill.
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), or
REVERSE (R) for a manual transmission.
5. If you have a four-wheel-drive vehicle with an
automatic transfer case, be sure the transfer case is
in a drive gear–not in NEUTRAL.
6. 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 won't move,
even when you're 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 (Automatic Transfer
Case)" in the Index.
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