Start with the road number
The locomotive number is often the fastest path to exact identification because railroads publish rosters and many models share similar bodies.
Look at the trucks
Four-axle B-B and six-axle C-C trucks immediately narrow the possibilities.
Study the radiator section
EMD and GE locomotives often have distinctive radiator shapes and overhangs that help separate model families.
Cab and nose shape
Wide safety cabs, high noses, low noses, windshield arrangements, and headlight positions provide useful clues.
Builder differences
EMD, GE, ALCO, Baldwin, and other builders developed recognizable design patterns over time.
Beware of rebuilds
Railroads frequently rebuild locomotives. A locomotive can retain an older body while receiving new electrical or mechanical equipment.
Keep exploring
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