Terex South Dakota Inc. is recalling nearly 6,800 1997-2009 model-year XT55 and XT60 aerial devices mounted on utility trucks because cracks may develop around the lower boom hinge pin boss at the turntable, the National Highway Traffic Safety Administration reported.

These cracks could lead to unexpected boom motion and cause the aerial platform to fall, NHTSA said.

Terex dealers will provide a preventive welding reinforcement to fix the problem, free of charge. The company can be reached at 1-605-882-4000.