Fiat Chrysler is adding more than 693,000 Ram pickups in the U.S. to a series of recalls to fix tailgates that can open unexpectedly.

The expansion covers certain Ram 1500, 2500 and 3500 pickups from 2013 through 2018 with power locking tailgates. Affected 2015 through 2017 trucks have 8-foot beds. The 2013, 2014 and 2018 trucks have beds of all sizes and were built before April 1, 2018.

Fiat Chrysler says it's not aware of any accidents caused by the problem.

A tailgate tab can fracture and cause the gates to unlatch, increasing the risk of cargo falling onto the road.

Dealers will repair the latch. Owners involved in the latest recall will get letters starting around Oct. 18.

AP wire services helped contribute to this report.