Mixed-traffic locomotive

A mixed-traffic locomotive is one capable of hauling both passenger trains and freight trains. The term is mostly used in the United Kingdom and those nations following British practise. Mixed-traffic locomotives were common in the early days of railway development, but later on more specialised locomotives were developed to haul the fastest passenger trains and the heaviest freight trains. Driving wheel sizes were generally intermediate, larger than the small wheels of most freight locomotives but smaller than the high drivers of express passenger locomotives.

The term was generally only used for steam locomotives, since most earlier British diesel locomotives were capable of hauling both passenger and freight trains.