North American Freight Railroad Parts Reference
Design Feature Codes, truck casting compatibility, spring specifications, and parts catalog — all in one place.
Design Feature Codes
Look up and filter AAR truck casting Design Feature Codes (DFCs) for side frames and bolsters.
Pairing Matrix
Check compatibility between side frame and bolster DFCs with our interactive pairing matrix.
Casting Patterns
Browse truck casting patterns by manufacturer, part type, and design feature code.
Spring Calculator
Find the right spring package for your car's load capacity and truck type.
Parts Catalog
Browse our reference catalog of freight car parts with specifications and supplier information.
Identify a Part
Look up a part by AAR number or manufacturer part number to find specifications and alternatives.
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