Jeep 2013 Grand Cherokee - Manual (Page 108)

2. To access the top tether strap anchorages behind the
rear seat, pull the carpeted floor panel away from the
seat back, this will expose the top tether strap anchor-
ages.
Pulling Down The Carpet Floor Panel
To Access Top Tether Strap
Top Tether Strap Anchorage (Located on Seatback)
106 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE