It seems that one of the items most sought after is the rear bumper for the 1965 - 1976 commercial chassis cars. This past weekend, I was given a rusted out rear bumper by Bill Marcy. After examining it, I now know why the rear bumpers rust out. At the bottom of the bumper is a 1" piece of steel that is formed at the bottom of the bumper face that is parallel to the ground, and then it makes a 90 degree bend upward to create a U shaped lip at the bumper bottom. This lip collects dirt till it is filled, and when it gets wet, the mud holds dampness in this channel. If you clean out the channel on a regular basis, your bumper will last forever. If not, then you are in risk of loosing your bumper on the road. I found that when the bumpers were made, that they used a 1/2" of weld at the top and the bottom to attach the rear bumper bracket. This is all that holds the bumper to the brackets that hold the bumper to the frame. When I picked up the bumper by the mounting brackets, one of them came off in my hand. This lead me to realize how weak the attaching method really is. If both lower sides of the bumper were badly rusted, then the only thing holding the bumper to the car is the two top welds, which are not very substantial. I can see how a rusted bumper could fall of the car while driving it, and the driver not realizing it till he got out of the car and walked to the rear.
I hope to send this bumper out for repair and re plating. I am waiting for a repair quote, which I hope will be reasonable.
I hope to send this bumper out for repair and re plating. I am waiting for a repair quote, which I hope will be reasonable.