Like the locomotive, the weight of the tender (and other cars) is carried on its frame, which runs lengthwise down the center of the "car body." The frame sits on special plates, called sills, onto which the tender trucks are attached. Frames on older museum cars may still be composite iron and wood sandwiches, but for common-carrier (interchange between railroads) service, one-piece all-steel frames are required by law.
Quick facts
Storage for "stuff"