Check the screws to make sure they are tight also. Last fall i was headed into town and doin about 45-50 and all of a sudden BOOM. I thought I had blown the engine for sure. Then I noticed the visor was gone. So I pull over back up and am picking up the center piece. I found all the parts except one of the yoke rods. Just as I am headed back to the truck someone pulls up behind me. Her front windshield has seen better days. Turns out its my house insurance agent. When the visor blew the centre piece hit her windshield as she was headed in the other direction. Just luck she did not loose it and go off the road. These old guys always require good walk arounds and nut and bolt checks.

1950 Chevy 1/2-ton 5-window