1938 Mercedes-Benz 540 K Streamliner
Explore the 1938 Mercedes-Benz 540 K Streamliner: programme history, design, verified rarity scope, specifications and credited photography.

The 1938 Mercedes-Benz 540 K Streamliner explores a different kind of pre-war performance from an open supercharged roadster. Its long enclosed form was an aerodynamic tool, not simply an ornamental body. Mercedes-Benz identifies it as a unique development vehicle associated with high-speed tyre testing, later returned to public view after substantial restoration work.
History and verified programme identity
The Streamliner belongs to the W 29 540 K context, but its purpose and body distinguish it from the wider model family. Mercedes-Benz describes an aerodynamically optimised one-off that served Dunlop. The manufacturer’s restoration account matters to any reading of present photographs: the car reappeared publicly in 2014 after restoration and reconstruction of its original configuration. A modern image therefore records the recovered historical design and surviving vehicle identity. It should not be captioned as proof that every visible panel has remained unchanged since 1938.
Engineering and design
The manufacturer’s aerodynamics history describes an aluminium body, a low silhouette, reduced surface disturbances and a covered underbody. It reports a drag coefficient of 0.36. That figure belongs to the maker’s historical account; it is not a new independent tunnel measurement. The design lesson is visible in the continuous roof and long rear section. Managing the air around an entire enclosed volume requires attention to many connected surfaces, including areas that a glamour photograph never shows. Underbody treatment is therefore part of the story, not an incidental detail. This specification belongs to the documented programme. It should be compared using the original measurement convention and the relevant configuration. A larger number copied from a different engine, market or racing derivative would describe a different car. Likewise, an engine change during restoration does not add another vehicle to the original production run. The distinction matters particularly when a model name appears in both road and competition histories: shared styling or ancestry can coexist with substantially different structures and equipment.
The physical car in the supplied photograph
Restored 1938 Mercedes-Benz 540 K Streamliner at Rétromobile 2015, with its enclosed body and open driver’s door visible.
What makes this version distinct
The Streamliner name describes this particular project. A standard 540 K with an elegant closed body is not automatically this car. Nor should a modern show appearance be given a new production date. The historical reference remains 1938, while the restoration and event dates belong in their own fields. Those distinctions preserve both the original engineering purpose and the modern conservation work.
Collecting and chassis evidence
A meaningful file for the Streamliner should connect original drawings and photographs with the restoration record. Note which elements were retained, which were reconstructed and how the restored shape was established. A carefully evidenced reconstruction of missing material is a historical fact to explain, rather than a reason to invent another original car. Start with the permanent chassis identity and a dated factory specification, then organise invoices, registration documents and photographs into a chronology. A recent photograph describes present appearance; the original delivery record establishes how the vehicle left its manufacturer. Record replacements and reversible changes without erasing their dates. For a limited edition, retain the allocation paperwork and edition plate together, since a badge alone cannot establish membership. Photographs of body seams, interior fittings and mechanical markings help a specialist understand changes across time. Where a vehicle has been repainted or restored, keep the earlier material alongside the finished appearance. A clearly documented change is more informative than an unsupported claim that every component has remained untouched.
Related Mercedes-Benz designs and meaningful comparisons
The SSK exposes its wheels and mechanical layout; the Streamliner integrates them into a flowing whole. F 200 Imagination later uses another striking coupé body to present research, but its central question concerns electronic controls. Both research cars make more sense when their specific engineering purposes remain visible.
Reading the sources
The programme sources and the photograph answer different questions. Manufacturer and custodial records establish the original model, Type, category and published production scope. The creator’s file establishes the pictured subject, setting and image permission. An individual chassis history can then add ownership, competition entries and dated repairs without changing the scope of the original programme. Build references are not survivor counts, and a later specification does not automatically become an additional newly manufactured vehicle. Where primary evidence does not establish a complete fabrication census, that field remains unassigned.
Specifications and rarity evidence
| Programme reference year | 1938 |
|---|---|
| Model / Type | 540 K Streamliner — W 29 |
| Body / competition role | Enclosed aerodynamic development coupé |
| Base programme | 540 K, W 29 |
| Body approach | Aerodynamically developed aluminium enclosure |
| Drag coefficient | 0.36, manufacturer historical account |
| Published build / register reference | 1 |
| Separately audited completed tally | Not assigned |
| Count scope | Manufacturer-documented 1938 one-off for high-speed development and Dunlop tyre testing. The restored/reconstructed original configuration is distinguished from untouched 1938 bodywork; no standard 540 K production total is assigned to this one-off. |
| Manufacturer / archive identity | Mercedes-Benz 540 K Streamliner |
Frequently asked questions
How rare is the 540 K Streamliner?
Manufacturer-documented 1938 one-off for high-speed development and Dunlop tyre testing. The restored/reconstructed original configuration is distinguished from untouched 1938 bodywork; no standard 540 K production total is assigned to this one-off.
How is 540 K Streamliner classified?
This is a manufacturer-documented historic development programme. Its original purpose, surviving vehicle history and later restoration are treated separately from ordinary customer road-production allocations.
Which technical details are established for the programme?
The primary record supports base programme: 540 K, W 29; body approach: Aerodynamically developed aluminium enclosure; drag coefficient: 0.36, manufacturer historical account. These are programme or explicitly attributed photo references. A particular surviving car’s engine, chassis repairs and competition preparation require its own dated documentation.
Does the photographed appearance establish factory originality?
The caption records a real creator-identified 540 K Streamliner subject and its documented setting. It establishes the illustration’s scope, while original components, restoration work and individual race provenance require chassis-specific evidence. A competition number, current paint or museum display is not used as an originality certificate.
What rarity or archive scope is verified?
Manufacturer-documented 1938 one-off for high-speed development and Dunlop tyre testing. The restored/reconstructed original configuration is distinguished from untouched 1938 bodywork; no standard 540 K production total is assigned to this one-off.
Who photographed the supplied image?
Thesupermat via Wikimedia Commons, under CC BY-SA 4.0. The original file and licence are linked with the image. Retain the creator, source and licence when uploading, exporting or reusing it; local retouching and synthetic enlargement have not been performed.
Related Mercedes-Benz profiles
Sources and photo credits
Photograph: Thesupermat via Wikimedia Commons original source, CC BY-SA 4.0. Original image or source-provided thumbnail supplied without local cropping, retouching or synthetic enlargement.
Built in limited numbers
Manufacturer-documented 1938 one-off for high-speed development and Dunlop tyre testing. The restored/reconstructed original configuration is distinguished from untouched 1938 bodywork; no standard 540 K production total is assigned to this one-off.
Gallery
Specifications
Factory specifications may vary by model year, market and configuration.
Identity & production
- Official model
- 540 K Streamliner


