GMC 2009 Yukon XL Owner's Manual page 29

Returning the Seat(s) to the Sitting
Position
To return the seat to the sitting position, do the following:
1. Pull the seat down until it latches to the floor. The
seatback cannot be raised if the seat is not latched
to the floor.
3. Lift the lever again to
release the rear of the
seat from the floor.
The seat will tumble
forward.
CAUTION:
{
If either seatback is not locked, it could move
forward in a sudden stop or crash. That could
cause injury to the person sitting there. Always
push and pull on the seatbacks to be sure they
are locked.
2. Lift the seatback and push it rearward. Push and
pull on the seatback to make sure it is locked.
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