5786 was built by the Great Western Railway in 1930 and, unlike many of its siblings, didn't get scrapped by British Railways, but was sold on to The London Transport Passenger Board .
 

5786 is one of over 800 57xx Pannier Tank locomotives built. They were used mainly for heavy shunting, short distance goods and branch line passenger duties.  Built at Swindon, 5786 entered service in January 1930 at Aberdare shed.  5786 remained in South Wales throughout its life with the GWR and BR(W).  Its last depot was Cardiff Canton.

In 1958 it was overhauled at Swindon and transferred to London Transport where it was painted Maroon and numbered L92.
The next eleven years were spent working maintenance trains, goods traffic and shunting from Lille Bridge and Neasdon Depots.
In the autumn of 1969 The Worcester Locomotive Society purchased it, in working order, from London Transport and it was transported by road to Severn Valley Railway (SVR), Bridgenorth.  It was steamed to Bewdley and restored to GWR livery.
During May 1970 the loco travelled in steam to Tyseley for a festival of transport and then returned to Bridgenorth, however it never worked on the SVR again.

It was moved by road to the Bulmer Railway Centre (BRC) at Hereford.
Since that time it was used turn about with other locos at the centre on passenger workings and for Brake Van rides.  When BRC closed in 1993, to make way for more factory space the Worcester Locomotive Society were warmly welcomed to Devon and 5786 completed a full season of service train working before it was stopped for a heavy general overhaul.  As can be seen from the pictures above this involved major reconstruction of the boiler, new tanks and the replacement of much of the copper pipework due to it having been stolen whilst at Bulmers.

5786 is now one of the SDR's main locomotives and can be seen regularly pulling service trains.