Chevrolet 2008 Tahoe Owner's Manual page 24

Manual Fold and Tumble Feature
Folding and Tumbling the Seat(s)
To fold and tumble the seat, do the following:
1. Make sure that there is nothing under, in front of, or
on the seat.
Notice: Folding a rear seat with the safety belts
still fastened may cause damage to the seat or the
safety belts. Always unbuckle the safety belts
and return them to their normal stowed position
before folding a rear seat.
2. Lift the lever, located on the outboard side of the
seat, to release the seatback.
1-20
The seatback will fold forward. Leaving the seatback
in this position creates a flat load floor.