Key takeaways
- On Rail runs no trains. The company leases, sells and manages vehicles – the running is done by the lessees.
- The DH 1004 is a rebuild, not a new-build: the frame, bogies and gearbox come from the V 100 class.
- Everything above the frame is new – the bodywork, engine and cab follow the style of modern shunting locomotives.
- Eight machines are the entire series. That makes the type one of the rarest diesel locomotives in German private rail operation.
- Build year isn't a clear-cut figure for rebuilds – log the rebuild year and the donor vehicle separately if you know both.
Contents
Fact file
| Full name | On Rail Gesellschaft für Eisenbahnausrüstung und Zubehör mbH |
|---|---|
| Headquarters | Mettmann, North Rhine-Westphalia |
| Role in the system | Lessor, dealer and rebuild originator – not a railway undertaking |
| Core business | Leasing, sale and management of wagons and locomotives |
| Best-known product | DH 1004, born from the concept of an affordable rebuild locomotive |
| Rebuild basis | Frame, bogies and gearbox of the DB Class V 100 |
| Executing works | The rebuilds themselves were carried out in a locomotive works in Moers, not in Mettmann |
| Current keepers | private railway undertakings and port railways – changing, check on the vehicle |
| Official website | www.on-rail.com/unternehmen |
Business areas
History at a glance
How to recognise On Rail
Does the train really belong to On Rail?
- Four axles on two bogies – the running gear form visibly comes from the V 100 family
- A cab between two bonnets, but styled in the form of modern shunting locomotives
- A mismatch between top and bottom – old running gear, new body; that's exactly the giveaway
- Radiator and exhaust section on the longer bonnet, clearly different from the V 100 original
- Vehicle number doesn't match the donor class – the rebuild gets a new number
- Keeper livery instead of railway colours: among the eight machines, virtually no two look alike
Strengths and weaknesses
What the company stands for
- An extremely small series – every sighting is a real find
- The vehicles have run with the same operators for years and are therefore traceable
- The mismatch between running gear and body makes the type recognisable at a distance
- A good practice case for telling rebuilds apart from new-builds
- Lessor-owned vehicles show how far a keeper and an operator can diverge
Where it falls short
- Very rare – anyone hunting for one deliberately needs patience and local knowledge
- The machines mostly work on works and port railway sites, so they're hard to view
- The build year is ambiguous: the frame and the body date from different decades
- There is no continuously maintained public source on the current fleet and condition
- A lessor never shows up in a train report – the company name says nothing about the operation
Updated: August 2026 – If you come across a modern four-axle shunter on a private siding that’s standing on bogies from the 1960s, you’re probably looking at a DH 1004. Behind this type stands On Rail of Mettmann – a company that runs no trains, owns no factory, and has nonetheless left its own locomotive type in the fleets of several private railways.
Don't just photograph rare rebuild locomotives – identify them
Number, location and date logged instantly – with a series of eight machines, every entry counts.
Lessor, dealer, concept originator
On Rail was founded in Mettmann in 1982 and has since worked in a field that stays invisible in operation: leasing, selling and managing wagons and locomotives. Companies like this decide which vehicles are even available to a small operator – but they never appear in a train report, because they don’t run trains themselves.
For spotters, that’s the crucial distinction. A vehicle’s keeper can be a lessor, while the operating railway undertaking running it is an entirely different company. One and the same locomotive can run for three different operators within a single year without anything changing on the frame or the number.
What remained of the V 100
In the mid-1990s, following railway reform, large numbers of withdrawn main-line diesel locomotives became available while private operators were looking for affordable traction vehicles. Out of this situation came the rebuild concept later built as the DH 1004. The rebuilds were carried out at a locomotive works in Moers.
| Assembly | Origin | How you can tell |
|---|---|---|
| Frame and bogies | Class V 100 | Bogie form and wheelbase as on the original |
| Gearbox | Class V 100 | Not visible, but noticeable in running behaviour |
| Engine and cooling system | New part | Different exhaust and radiator arrangement than on the V 100 |
| Bodywork and bonnets | New part | Styling of the 1990s MaK shunting locomotives |
| Cab | New part | Larger window areas, a more modern cut |
| Vehicle number | Newly assigned | Doesn’t fit into the donor class’s number series |
The comparison is worthwhile: picture a Class 212 next to a MaK G 1205 BB. The DH 1004 sits exactly in between – one thing below, another above.
Log two years for rebuilds
A rebuilt vehicle has no single clear build year. Keep the rebuild year and, if known, the donor vehicle's build year separately. This ambiguity is exactly what causes contradictions between different sighting lists – anyone who separates them cleanly won't need to correct anything later.
How far apart are the frame and the body?
Both figures are correct – which is why both belong in the sighting.
Works, transfer and test runs
A rebuild passes through the same stages as a new-build – it just doesn’t start in the factory, but on a siding.
Source the donor vehicle
Withdrawn machines often stand stored for years. Anyone who knows such locations sees vehicles that vanish again shortly after – see lists of stored locomotives.
Transfer to the works
The vehicle is hauled or transferred under its own power, usually unmarked and in poor visual condition.
Rebuild and new bodywork
The frame and bogies remain, everything above is newly built. During this phase the vehicle effectively doesn't exist as a locomotive.
Testing and acceptance
Test runs precede certification. Only afterwards is the new vehicle number assigned – the old one no longer applies.
Handover to the lessee
Livery and markings follow the keeper, not the rebuild works. That's why eight machines of the same type all look completely different.
Eight machines, one goal
Anyone wanting to document a rare series completely needs a logbook, not a photo folder.
Rebuild or new-build? The decision at the trackside
Points to a rebuild if …
- the running gear and body visibly come from different eras
- the vehicle number doesn't fit the visible type
- the frame and bonnets show different degrees of ageing
Stays unclear if …
- the vehicle is freshly repainted and all traces are hidden
- only one side was visible
- the works and rebuild plates are missing or painted over
It's a new-build if …
- the running gear and body come from a single continuous design
- the number fits cleanly into a known new-build series
- the works plate names the manufacturer and build year without contradiction
Today the machines run with private railways in the west – among them the Rurtalbahn and the NIAG. Anyone hunting deliberately has better odds at freight hubs like Duisburg-Hochfeld Süd than at a passenger station.
Port and industrial railways are not public land
The most interesting locations for these machines lie on siding, port and industrial railway sites. House rules apply there, and shunting operations carry considerable danger. Observe only from publicly accessible areas – the basics are covered in the article on house rules.
Verdict
On Rail is a good example of how the railway industry has more layers than are visible at the trackside. A lessor with no trains and no factory of its own has left behind a locomotive type that doesn’t exist anywhere else – born out of an economic situation that only occurred once.
For you, that leaves a transferable rule: when the running gear and body don’t match, that’s not a flaw in your observation, but the real information. Log both, and your sighting is worth more than a clean photo without a number.
Verdict in short
The DH 1004 is a rebuild locomotive: V 100 running gear, new 1990s bodywork, eight examples. On Rail itself is a lessor and keeper, not an operator – who's running the train is shown in the data panel, not the company name.
Log what you actually saw
Type, number, keeper and date recorded separately – so even a rare rebuild locomotive stays clearly identifiable.
Summary
- Leasing and trading form a level of their own within the system: they decide which vehicles are available at all, but never appear in operation.
- Rebuilt vehicles are the best illustration that a vehicle can consist of several generations at once.
- The DH 1004 is therefore more interesting than its small numbers suggest – it explains an entire procurement logic of the 1990s.
- For the sighting, the same rule applies as everywhere in the end: the full vehicle number, not the company name.
Frequently asked questions
Is On Rail a locomotive manufacturer?
Not in the classic sense. The Mettmann-based company is above all a lessor, dealer and manager of wagons and locomotives. The rebuild concept behind the DH 1004 came from this house, but the rebuilds themselves were carried out at a locomotive works in Moers. This separation of concept and manufacture is no exception in the industry.
What was a Regio-Lok?
That's the name of the concept from which the DH 1004 emerged: a locomotive that reuses existing substance instead of being built from scratch. The idea was economic – after railway reform, many withdrawn V 100 machines became available while private operators were looking for affordable traction.
What was actually reused on the DH 1004?
The frame, bogies and gearbox come from the V 100 family. The bodywork, engine and other equipment are new parts and follow the styling of the MaK shunting locomotives of the time, such as the MaK G 1205 BB. That very mismatch makes the vehicle recognisable: a classic of the 1960s underneath, a vehicle of the 1990s on top.
How many DH 1004 are there?
Eight machines were built between 1997 and 2003. The series then ended because new-build locomotives from the Vossloh G family – such as the Vossloh G 1000 BB – served the same market on comparable terms. There's no reliable ongoing source on the current condition of each individual vehicle.
Where do the vehicles run today?
With private railway undertakings and port railways in western Germany, including the Rurtalbahn, the NIAG and the Westerwaldbahn. Keeper changes are common with such small series, though – always check the allocation on the vehicle.
Why do companies lease locomotives at all?
Because traction is expensive and demand fluctuates. An operator who only occasionally needs an extra locomotive doesn't buy one – they lease it. For you at the trackside that means: the vehicle belongs to a lessor, while the train is run by an entirely different company. How to tell the two apart is explained in the article Who's actually running it?.
Which build year belongs in my sighting?
Honestly, both. Log the rebuild year as the vehicle's build year in its current form and, if known, the donor vehicle's build year as an addition. A single year figure is almost always misleading for rebuilds, and that's exactly what causes contradictions between different sighting lists.
How do I generally recognise a rebuilt vehicle?
By its contradictions. A modern body on a visibly older running gear, a vehicle number that doesn't fit the recognisable type, different ageing on the frame and the bonnets. For older diesel locomotives, comparing them with the original is worthwhile – the article on older-generation diesel locomotives shows what the unaltered types look like.
Does On Rail also lease wagons?
Yes, wagons are part of the core business. For spotters that's harder to grasp than a locomotive, because wagons are documented less often. The markings on the wagon reveal type, keeper and area of use – how to read that is covered in the article on wagon types.
Are rebuild locomotives technically worse than new-builds?
That can't be said across the board and wouldn't be a credible answer without reliable operating data anyway. Only the economic core is certain: a rebuild saves the cost of a frame and running gear but inherits its age and wear history. Whether that pays off depends on the duty profile – light shunting work is different from main-line service.
Log vehicles from On Rail
Company, vehicle, location and date logged in seconds – and visible to the community.
The operational level in the railway operator database
Who actually runs the trains, with keeper markings and identifying features on the vehicle.
Rurtalbahn GmbH
Rurtalbahn GmbH operates on lines in western Germany. This page explains a feature typical of such lines: the level crossing.
FreightNiederrheinische Verkehrsbetriebe AG (NIAG)
The Niederrheinische Verkehrsbetriebe AG carries region and legal form in its name. Its railway side lives – like many private operators – on locomotives with a history.
FreightWesterwaldbahn GmbH des Kreises Altenkirchen (WEBA)
Westerwaldbahn GmbH des Kreises Altenkirchen carries both a landscape and a district in its company name. Together, they give one of the most precise location clues a railway name can offer.
FreightRheinCargo
A company name built from region and business area – and behind it, the pattern of a jointly held company. What that means for the fleet, markings and your sightings.
Typical vehicles
OnRail DH 1004
The OnRail DH 1004 is a four-axle diesel-hydraulic locomotive from a small batch – rare in the fleet, but easy to identify by its shape.
ClassDB Class 211 (V100)
The Class 211 is the lighter version of the West German V 100, classified as V 100.10 until 1968. Here's how to recognise it and place it correctly.
ClassDB Class 212 (V100)
The Class 212 is the more powerful West German V 100, classified as V 100.20 until 1968. Here's how to identify it and tell it apart from its sister classes.
ClassMaK G 1205 BB
The MaK G 1205 BB belongs to the 1200 series from Kiel. The final digit of the type number is the key: it separates successive design stages.
ClassVossloh G 1000 BB
The Vossloh G 1000 BB is one of the most frequently seen diesel locomotives of private operators: four axles, diesel-hydraulic, with a centre cab and two hoods of unequal length.
ClassLEW V 100
The LEW V 100 from Hennigsdorf still shapes the operations of many private railways today. Rebuilds and re-engining make identifying it both interesting – and tricky.
Where you will find On Rail
Spotting locations where you will regularly come across vehicles from this organisation – with viewpoints, the best light and coordinates.
Duisburg-Hochfeld Süd
Duisburg is the freight hub of the Ruhr region, and Hochfeld Süd is the point where the trains cross the Rhine. If you're after heavy freight trains, port traffic and locomotives from private operators rather than ICE units, you'll find one of Germany's busiest freight lines here.
Border stationAachen West
Aachen West is the freight yard on the axis towards Belgium. Here trains bound for Antwerp change electrification system, locomotives are swapped and crews change over – and it's all watched exclusively from public roads and bridges.
More companies
Vossloh
In spotting logs, Vossloh stands for a whole family of diesel locomotives – and today builds not a single one any more. The company has long since shifted to rail fastening, points and rail machining. The G-locos keep running regardless, under new owners.
ManufacturerRailtec Eisenbahntechnik
Railtec Eisenbahntechnik in Marl overhauls used shunting locomotives, hires them out and sells them. Independent workshops like this are why machines from the 1960s are still in service – and their traces can be read straight off the vehicle.
ManufacturerPACTON
PACTON, based in Ennepetal, trades in secondhand diesel locomotives, road-rail vehicles and railway construction equipment, and transports rail vehicles by road. A small company in a niche that explains why some locomotives change operators without covering a single mile of track.
ManufacturerGmeinder Lokomotiven
Gmeinder of Mosbach never built an ICE, but for decades it built the vehicles that shunt at every works site and every port. Once you understand its type scheme of drive, power class and wheel arrangement, a small locomotive tells you more than many a main-line locomotive.
Related guides from the blog
- Class 218 and Ludmilla: Identifying and Finding Classic Diesel Locomotives
- Reading the UIC number: what the 12 digits on a vehicle reveal
- Who's Actually Running That Train? How to Identify Railway Operators
- Identifying Freight Wagon Types: From Habbiins to Sgns
- Identifying Train Classes: How to Recognise Any Locomotive or Multiple Unit
