I live in the suburbs where mail delivery is by a box at the side of the road at the end of my long driveway. In 1986, we placed a standard wooden post in the ground and mounted a generously sized mailbox to it. Four years later, that post bit the dust as a pickup truck ran it down.
The mailbox survived. My husband, determined not to have to replace the post so often, built a post of a larger size of pressure treated lumber that has lasted until recently.
Last year I had to replace the mailbox because the old one had literally cracked from weathering. Late last month I noticed that the mailbox post was leaning. The lean was a little more pronounced as the days passed. I gently pushed against the post and it moved. The base had rotted out and the post would need to be replaced.
I went to investigate my options. I could buy a whole new mailbox with an integrated newspaper slot, but I would also need to buy a wooden post. The other option was to buy a post for the current mailbox that was actually made for that mailbox.
I came home with the new mailbox post and a 50 lb bag of quick-set concrete. I read all the necessary directions and set about digging the new hole for the new post. I managed to dig half of the hole in one morning before the weather turned too hot for me to continue working. The next morning I was able to dig the hole to a proper depth.
Leveling the post was easy enough; I used the concrete mix to hold the box in place before wetting it. After four hours, I had successfully transplanted the mailbox. The newspaper tube would not be so lucky. My husband had decided that it would not come loose ever. He used about a dozen screws and some serious glue to attach it to the old post. Fortunately, the newspaper customer service people were understanding and are sending me a new tube.