This 1948 Oldsmobile fastback is in poor shape. We see rust in many locations.

We can identify the 1948 model year by the metal gravel shields (guards) and the round badge on the hood (not visible on the images). 1948 was the last year Oldsmobile offered the old, prewar style.

Pontiac had the same (GM) body style. Compare it to this post card image.

The '8' on the back indicates, it is 8 cylinder car. Because the bumpers are wrapped around the car body, it indicates a model '78'. (If the bumper were straight, it would be a '68' type.)

Here we can see severe rust damage in the trunk area: