The last car in the train was the caboose for many years. Is that what you were referring to? I don't know of any other name for a small platform at the back of a rail car. Politicians would stand on the back platform of a normal car when touring the state or country while running for election many years ago. But I am not aware of any special name for the platform of a railroad car.
I think it's known as the verandah, borrowing the architectural term.
Platform
The outside of an egg is called the shell.
Each part of a train is called a car.
The engine. The driver is called the engineer.
rim
The outside part of an egg is called the shell. It serves as a protective covering for the egg's contents.
margin
you see the out side of it which is called the base or the outside
If it's a powered locomotive, then a locomotive. If it's a car with a cab to control the train, then a cab-car. If it's a train powered by itself, called a Multiple Unit (MU) with the engine part of the train, the front is called, well, the head end.
Platform is a noun.
The last part of a train is a caboose.
Volar: Pertaining to the palm or the sole. For example, the volar surface of the forearm is theportion of the forearm that is on the same side as the palm of the hand.