Dodge 2016 Grand Caravan Owner's Manual page 301

Make sure the directional arrows on the crossbars align
with the directional arrows on the side rails. Set the
crossbars into the deployed positions.
Crossbar To Side Rail Installation
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 299
Once the crossbars are set into position, tighten the
thumb screws completely.
Tightening Crossbar
3