Northern Spirit inherited a large fleet of Class 158 units, many of which were used on TransPennine Express services, with others used on West Yorkshire Metro-sponsored services.  The final ten units were built specifically for West Yorkshire PTE Metro services around Leeds. Prior to the introduction of the Class 220 and 221 Voyagers, Virgin CrossCountry operated a small number of Class 158s, numbers 158747-158751. Following privatisation, Central Trains operated these services but quickly procured a large fleet of Class 170 Turbostar units for such services and transferred the Class 158 fleet to secondary routes such as Birmingham New Street to Hereford and Derby to Matlock. , In 1990–1991, BREL built six 3-car ASR class units based on the Class 158 for State Railway of Thailand. The lorry driver had forgotten to fully lower the tipper body after delivering materials to a site next to the railway, and drove into the footbridge, knocking its superstructure onto the track.  By the end of 2006, a total of 16 units (158815-158817 and 158842-158854) had returned to the leasing company as Arriva gained exclusive use of the entire Class 175 Coradia fleet which had previously been shared with other train operators. , As built, interiors were described as fully carpeted, with "panoramic" windows and a variety of seats arranged both airline-style and in bays of four around tables.
.  During late 2007 and early 2008, the FGW Class 158 Express Sprinter fleet was refurbished. Examples included long-distance TransPennine services in the north of England, as well as a range of upgraded regional services under the Alphaline brand in the Midlands, Wales and the South West. They were built to replace many locomotive-hauled passenger trains, and allowed cascading of existing Sprinter units to replace elderly 'heritage' DMUs. The fleet has now gained a permanent blue-and-white livery based on the Scottish Saltire, after Transport Scotland announced in September 2008 that it was specifying a permanent livery for all Scottish trains, which would not be changed in the event of a change of franchisee. , WiFi was fitted in 2017, and Persons with Reduced Mobility modifications began in June 2018, with toilet retention tanks also being fitted.
The class has also suffered from unreliable air-conditioning systems since the outlawing of the CFC gases with which they were originally designed to work.
CLIENT: South West Trains, East Midlands Trains, Arriva Trains Wales, Abellio Scot Rail. Units regularly appeared on off-peak workings between Birmingham and Manchester, and also on Sunday mornings between Birmingham and Doncaster.  The Class 159 DMUs are almost identical to the Class 158s, having been converted from Class 158 to Class 159 in two batches to operate express services from London Waterloo to the West of England. , The Class 158 Express Sprinter Units were introduced to the East Midlands by Regional Railways Central to replace the Class 156 SuperSprinter on long-distance express services branded as Alphaline, such as Norwich to Liverpool Lime Street via Nottingham. The project was sponsored by Porterbrook Leasing to integrate into the C6 overhauls for their 158 fleet. Following a franchise change, all Northern units were passed to Arriva Rail North in April 2016. , The Class 158s were expected to achieve 13,500 miles (21,700 km) of operation between major services and a range of up to 1,600 miles (2,600 km) from each refuelling.. Door system safety has been maintained. Unlike the purpose-built three-car Class 158s and Class 159 units, the centre car was a Driving Motor with the cab locked out of use and an adapter to connect the different-sized gangways. Train Door Solutions Ltd. (TDS) was formed in 1999 and is now one of Britain’s leading independent engineering companies for the design and maintenance of train door systems. The DMU hit the footbridge debris approximately one minute later. , Until this refurbishment, the fleet had seen only minor attention to its interior since a refit by Wales & West in the late 1990s (little more than the fabric on the older seats changed and CCTV fitted) as well as having been only partially repainted into Arriva colours externally. , South West Trains and East Midlands Trains livery, 2005 onwards, Great Western Railway 3-car livery, 2015 onwards, South Western Railway livery, 2017 onwards, East Midlands Railway livery, 2019 onwards. British Rail Central Advertising Services: "Your New Train is Here", January 1991. .  Despite initial problems in retro-fitting the necessary 'glass cockpit'-style driver controls, Arriva's Class 158 Express Sprinter units became the first fleet in the UK to be equipped for regular use with the ETCS Level 2 signalling system. East Midlands Trains (EMT) had a fleet of 25 units inherited from Central Trains, with some units transferred from First Great Western and South West Trains.  These were employed on Glasgow Queen Street to Edinburgh Waverley services, as well as services to Aberdeen and Inverness.  Following the introduction of newly built Class 170 Turbostar units on primary express services in 1999, the Class 158 fleet was reduced in number by six, with those remaining cascaded away to secondary routes such as the Far North Line. At the same time, the units' engines were overhauled and the units repainted in FGW's own lilac and blue colours.. When the units were replaced by the Voyagers, the units transferred to Wessex Trains, with one unit transferring to First TransPennine Express. On 1 February 2008, the same unit 158856 collided with debris from an overline footbridge, which had just been accidentally demolished by a tipper lorry, near Barrow-upon-Soar. On 14 October 2018, these units transferred to Transport for Wales. A small batch of units numbered 158747-158751 were used by InterCity to supplement its core fleet on some cross-country services, mainly from the North West to Scotland, but also to Portsmouth. Several of the ScotRail units have had names attached - for example 158702 is named BBC Scotland - 75 Years, 158707 is named Far North Line - 125th Anniversary, 158715 is named Haymarket and 158720 is named Inverness and Nairn Railway - 150 Years.  Successor companies Wales & Borders (2001) and Arriva Trains Wales (2003) continued to use this type of unit on similar workings, with a total allocation of 40 units also allowing Cambrian Line services to become entirely Class 158-operated. South Western Railway operates Class 158s 158880-888 and 890. In 2018, the additional 8 units acquired by Scotrail from other TOCs were transferred to Northern in stages - the first two occurring in February 2018 and the remainder in December 2018. The TDS system provides direction and speed control, obstacle detection, speed locking, crew access and emergency egress. In 2018, Northern acquired an additional 8 Class 158 units from Abellio Scotrail; the first few units transferring in February 2018 with the remainder in December 2018. 158782, 158784, 158786–787, 158789–797, 158815–817, 158842–845, 158848–851, 158853, 158800–801, 158803–805, 158807, 158809, 158811, On 3 December 2005, unit 158856 was involved in an accident at. Despite an increased top speed of 90 mph (145 km/h), the units also promised a smoother, quieter ride than its predecessors. Funded by the Welsh Assembly Government at a cost of £7.5m, work completed included interior and exterior repainting, along with replacement of seating, wall coverings, carpets, lighting, luggage racks and toilet fittings. Unit 3 Garamonde Drive A number of 158s are currently sponsored by Merseytravel despite the fact that they do not go near Merseyside. TDS is also able to offer a full overhaul of the main door actuator. Depending on the adjustment of the door pins some Class 158 doors really bang when they open.  Following privatisation, many operators undertook to re-engineer or entirely replace such equipment. This allocation was then made permanent in August 2017 following Stagecoach's loss of the South Western franchise to South Western Railway. 158770, 158773–774, 158777, 158780, 158783, 158785, 158788, 158799, 158806, 158810. . After the privatisation of British Rail, the Class 158 fleet was divided among several franchises. Milton Keynes The original ScotRail franchise applied its own livery to the Class 158s, followed by a further repaint by First ScotRail after it took control of the franchise.  Commercial operation under ETCS started on 28 March 2011.
The new system is designed as a direct replacement for the existing system.  Interiors have also seen attention on more than one occasion.