What the rubber bumper is going on in 74

TSB about them at these pages;

http://www.hamtramck-historical.com/images/TSBs/1974/23-06-74D page1.jpg

http://www.hamtramck-historical.com/images/TSBs/1974/23-06-74D page2.jpg

http://www.hamtramck-historical.com/images/TSBs/1974/23-06-74D page3.jpg