The Engineering Department

Underneath all this is a Leyland Titan PD2 chassis dating from 1949, formerly double decker No 50 (OXR 150) with Weymann bodywork.  It was rebuilt as a recovery vehicle in 1967, largely using parts from the Duple bodywork from AEC Regal No 2.  It was withdrawn in 1981.
E7 was a Deansgate bodied Mercedes L407D which was originally minibus No 35 (TKN 35S), part of a batch of seven which entered service in 1977.  They were withdrawn after a relatively short life in 1980, but this one was retained by the Engineering Department, while all the others were sold.  It was in use until 1997, when it went for scrap at the ripe old age of 20!
Formerly coach number 25 (HRP 425H), this Plaxton bodied Leyland Leopard was converted to a recovery vehicle in 1981, receiving the crane unit from the former E1 (above) which was withdrawn in that year.  After operating on trade plates for many years, E8 was registered Q108 AKN.  It was withdrawn from full duty in 2014, but is retained as part of the small collection of service vehicles associated with the Heritage fleet..
Since the war, there has always been at least one Landrover in the Engineering Department fleet.  Although not full recovery vehicles, these versatile machines are quite capable of towing a broken-down bus out of the way, until a more permanent recovery can be made.  This long-wheelbase Landrover pick-up, E9 (C224 EKN), was bought new in 1986, and was in use until 2014, when it was replaced by E19 (DA14 RFP), a broadly similar Landrover Defender, but with a hard top rather than the canvas tilt as seen here.
The ubiquitous Ford Transit Van.  E10 (J130 CKN) was bought new in 1991, and was withdrawn in 2014.
This 1988 Mercedes recovery vehicle, E11 (F234 OKN), was acquired in 1995 as part of the takeover of Heygate Commercial Vehicles, and was in use up until 2012.  Note that Eldorado operates a commercial heavy recovery service, as well as using the vehicles for its own fleet when necessary.
This former Plaxton Beaver bodied Mercedes midibus, E12 (M874 NOL), is not an Eldorado fleet cast-off, but was acquired in 2001 specifically for its role with the Engineering Dept., and was withdrawn in 2010.
E13 (DA02 BNX), a Scania R144 recovery vehicle was acquired new in 2002, and was withdrawn in 2014.