Pop the rear window and run some rope or bungees around the frame and secure it under the rear somewhere.
You should be fine as long as your not driving long distance or on the highway.
2014 - Altitude - Billet Silver
Silverstar Ultra - Lows and Fogs, 15% Tint,
Mopar Slush Mats & Cargo Mat, Curt Hidden Hitch,
Blk Lug Nuts, Blk Overland Mesh, 1.25" Bora Spacers