Yep, Jim, before I joined the police department, I worked for the post office in Dallas and a friend and co-worker had a Packard sedan and that was the first car I ever saw with the automatic levelling. Even without the engine running, if you loaded something heavy in the trunk, or just sat on the trunk, after a few seconds you could hear a little electric motor start up and it would raise the back end up level. And of course when you removed the load, the springs would let the back end raise up and in a few seconds that little electric motor started again and lowered the back end to level again.
I don't remember what year model it was, maybe about 1934, but my parents always said one of the cars they had liked best was an old used Packard limousine they bought when I was a baby. They said you could sit in the back seat and stick your legs straight out in front of you without touching the back of the front seat.