Not only does the '38 have less grille bars than the '37 but the grille is also more vertical which makes the hood longer. I thought the left side side-mounted spare on the closest car looked odd - I think it possibly doesn't have a full size wheel in it as I can see in one of the other pics that the one on the other side looks alright. It is difficult to be certain but I suspect these cars are Roadmasters. I think there may be three of them?