Rolling stock › In serviceData updated
Class 171 Turbostar unverified
Southern's only diesel trains: Turbostars that run from London Bridge to Uckfield and on the Marshlink line between Eastbourne, Hastings and Ashford International. They were built as Class 170s. They became 171s when they were given Dellner couplers, the type the Electrostars use, so that the two kinds of train can be coupled in an emergency.
- Type
- Diesel multiple unit
- Builder
- Adtranz / Bombardier Transportation, Derby
- Built
- 2003–2005
- In service
- since 2003
- Operators
- Southern
- Formation
- 3 cars (171/8 and 171/2) or 2 cars (171/7)
- Trains in fleet
- 17
- Fleets
- Southern: 47 diesel vehicles, run as three- or four-car trains between London Bridge and Uckfield and between Eastbourne and Ashford International
- Top speed
- 100 mph
- Power
- Diesel-hydraulic: an MTU 6R 183 TD13H engine (315 kW) with Voith transmission under each car
- Car height
- 3.77 m
- Car width
- 2.69 m
- Profile
- main-line
- Walk-through
- Yes
- Air-conditioned
- Yes
- Total capacity
- Porterbrook (2013) gives per car: DMCL 9 first and 43 standard, DMSL 64, MS 74; seat totals for today's units haven't been published outside Wikipedia
- Status
- In service: 47 vehicles at 31 March 2025.
This page is marked unverified: its figures haven’t yet been confirmed by an official source or a published history. The foot of the page says what’s in doubt.
Car types
| Code | Car | Length | Doors per side |
|---|---|---|---|
| DMCL | Driving motor composite with lavatory (DMCL) | 23.62 m | 2 double |
| MS | Motor standard (MS) | 23.61 m | 2 double |
| DMSL | Driving motor standard with lavatory (DMSL), in two-car 171/7s | 23.62 m | 2 double |
Sources
- Class 170 & 171 Diesel Multiple Unit (edition 1A), Porterbrook Leasing, September 2013, pp. PDF pp. 23-27 (brochure pp. 44-53) (171/7 (10 two-car) and 171/8 (6 four-car) data sheets: car lengths, width 2.69 m, height 3.77 m, MTU 6R183TD13H 315 kW per car, 100 mph, Dellner outer couplers, two bi-parting plug doorways a side at 1/3 and 2/3, seats per car, P3-23 and T3-23 bogies, build dates; layout diagrams (plans) of each car)
- Class 170 and 171, Eversholt Rail (Class 171 at GTR, three-car DMCL-MS-DMCL; DMCL 23.6 m, MS 23.61 m; 100 mph)
- Table 6314: rolling stock vehicles by traction type and operator, Office of Rail and Road, 20 November 2025 (GTR's 47 diesel vehicles at 31 March 2024 and 2025)
- Audio description guide: Southern 171 Turbostar trains (archived), Govia Thameslink Railway (routes; Southern's only diesels; two sets of doors a side; first class at the ends; accessible toilet in an end car)
- Classes 170 and 171, Southern Electric Group (sremg.org.uk) (built as 170/7s for Govia's South Central, delivered to Selhurst from August 2003; first passengers 8 December 2003; converted to Dellner couplers and renumbered 171; 171730 was 170392)
- More DMUs for Southern, Rail, 29 October 2014 (four three-car ex-ScotRail 170s to Southern in 2015 for the Uckfield line)
- TURBOSTAR - United Kingdom (project page: overview, technical data, technical drawing), Bombardier Transportation (archived copy), archived 18 February 2016 (Voith transmission and ZF final drives; aluminium body with bolted steel ends; sliding-plug doors)
- British Rail Class 171, Wikipedia, accessed 6 October 2026 (today's unit numbers and the 2022 reforming)
- Abellio ScotRail branding guidelines: ScotRail rolling stock exteriors, Transport Scotland, 27 January 2016, p. 8 (the Class 170 outline the drawing uses)
- Class 171 photographs (171721 at Pevensey & Westham, 171724 at Cheesemans Green, 171727 at London Bridge), Wikimedia Commons (CC BY-SA 2.0 and CC BY-SA 4.0; Southsea_Matt), 2014-2025 (Southern's colours (171 721, 171 724, 171 727))
unverified today's fleet of 17 units is from Wikipedia: four two-car 171/7s (171727-730), twelve three-car 171/8s (171801-812) and one three-car 171/2 (171201). It matches ORR's count of 47 GTR diesel vehicles, and Eversholt lists its Class 171 at GTR as three-car DMCL-MS-DMCL, the 2022 reforming is from Wikipedia. One middle car from each four-car 171/8 (171801-806) went into a two-car 171/7 (171721-726), and those units became 171807-812; two 171/2s and two 171/4s went to EMR. GTR's guide still says 'three or four carriages', MS length: Eversholt gives 23.61 m; Porterbrook's 2013 data sheet rounds it to 23 m, build dates: Porterbrook's 2013 list dates the 171/7s from July 2003 to April 2005 and the 171/8s from May to September 2004; the Southern Electric Group says the 171/8s came in 2006, 171201 was built earlier, as a ScotRail Class 170/4, and joined Southern in 2015 (Rail, 2014; its build date isn't in the sources read), the drawing: the Class 170's measured body (no 171 drawing has been published), in Southern's colours from photographs