Rear Seat Belt problems of the 2005 Dodge Ram 3500

I was utilizing my vehicle for a child safety installation class. During the class all three of the rear seating positions were utilized for installation of child safety seats. During installation, following the instructions outlined in my owners manual, all three rear seatbelt locking latch plates broke. I had this problem back in 2005 when I installed my daughter in her car seat in the right rear seating position. Back in 2005, the right rear seatblet position was repaired under warranty. Each of these times a small piece of plastic breaks off, resulting in the seatbelt latch plate no longer being able to lock. This feature is only utilized to lock the seatbelt during the installation of a child safety seat and had I not been some-what mechanically inclined, I might have not realized the seatbelt had been rendered inoperable for safe installation of a child safety seat.