Cadillac 2010 DTS Owner's Manual page 311

If you put things inside your vehicle, like
suitcases, tools, packages, or anything else, they
will go as fast as the vehicle goes. If you have to
stop or turn quickly, or if there is a crash, they will
keep going.
Things you put inside your vehicle can strike
and injure people in a sudden stop or turn,
or in a crash.
Put things in the trunk of your vehicle. In
a trunk, put them as far forward as you
can. Try to spread the weight evenly.
Never stack heavier things, like
suitcases, inside the vehicle so that some
of them are above the tops of the seats.
Do not leave an unsecured child restraint
in your vehicle.
When you carry something inside the
vehicle, secure it whenever you can.
This feature keeps the rear of your vehicle level
as the load changes. It is automatic, you do not
need to adjust anything.
This type of level control is fully automatic and will
provide a better leveled riding position as well as
better handling under a variety of passenger and
loading conditions. An air compressor connected
to the rear shocks will raise or lower the rear of
the vehicle to maintain proper vehicle height.
The system is activated when the ignition key is
turned to ON/RUN and will automatically adjust
vehicle height thereafter. The system may exhaust
(lower vehicle height) for up to ten minutes after
the ignition key has been turned to LOCK/OFF.
You may hear the air compressor operating when
the height is being adjusted.
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