Dodge Grand Caravan 2018 Owner's Manual page 126

124 GETTING TO KNOW YOUR VEHICLE
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
Once the crossbars are set into position, tighten the thumb
screws completely.
Tightening Crossbar