Same photo of my grandfather plus the photo of my uncle on the back of the Southern Tire Company Truck. I know from city directories and from the apparent age of my uncle that my GF worked there at least from 1925 to 1932, probably longer.
The vintage tire advertising is from Vintageadbrowser.com. You can browse ads by decade at that site. The detail is hard to see here but the ad in the top right is for PA Tires (never heard of it) and the tread looks just like the tires in the photo which have odd little round suction looking thingys (like and octopus!). There is a Federal banner hanging next to my GF arm. The back of the truck says Mohawk Tires.