The company says in documents posted Tuesday by the National Highway Traffic Safety Administration that water can get into the electronic gate release switches, causing the gates to unlatch. If that happens, cargo can fall into the road and become a hazard.
The trucks in the new recall were added after the company found 237 field reports of tailgates opening unexpectedly. Until repairs are made, GM says owners should check to make sure the gate is closed and latched before driving.
Dealers will replace the exterior touch pad switch assemblies with new ones that are more resistant to water.
Owners will be notified by letter starting on Jan. 13.