British United Traction

British United Traction (BUT) was a joint company owned by the Associated Equipment Company and Leyland Motors which produced railway equipment and trolleybuses. It was established in 1946.

British United Traction was a major supplier of diesel engines for British Rail's first-generation diesel multiple units. These engines were built in 125 hp (93 kW), 150 hp (110 kW) and 230 hp (170 kW) versions and were branded "AEC", "Leyland" or "Leyland-Albion".

A 275 hp (205 kW) version was supplied to Ulster Transport Authority for their UTA MPD class railcar.

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