GMC 2006 Yukon XL Owner's Manual page 9

Front Seats
Manual Seats
CAUTION:
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You can lose control of the vehicle if you try to
adjust a manual driver's seat while the vehicle
is moving. The sudden movement could startle
and confuse you, or make you push a pedal
when you do not want to. Adjust the driver's
seat only when the vehicle is not moving.
If your vehicle has a manual bucket or a split bench
seat, you can adjust the seat forward or rearward with
the bar located under the front of the seat cushion.
Lift the bar to unlock the seat. Slide the seat to
where you want it and release the bar. Try to move
the seat with your body to be sure the seat is locked
in place.
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