GMC 1996 Sierra Owner's Manual page 11

Reclining Seatbacks
Your vehicle will have one of these reclining
seatback controls.
To adjust a seatback with this lever, move the lever
rearward. Release the lever to lock the seatback where
you want
it.
Move the lever again rearward and the
seatback will go to an upright position.
To adjust a seatback with
this lever, lift the front of
the lever.
Release the lever to lock the
seatback where you want it.
Pull up on the front of
the
lever and the seatback will
go to an upright position.
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