M04
Inline-6- 04 3.1 L · 3,131 cc
56 PS
41 kW · 55 hv / 3,200 r/min
162 N·m
119 lb·ft / 1,200 r/min
Mercedes-Benz Executive Sedan · Typ 300 / 320
The 12/55 PS line, briefly continued into 1928.

Arriving in 1927 as a continuation and enlargement of the Typ 300 line, the 300/320 shared the engineering philosophy of its predecessor while offering coachbuilders a more generous platform for formal saloons and open touring bodies. It sat in a transitional moment, as Mercedes-Benz sorted its model hierarchy for the late 1920s.
Production was brief and modest: just 202 examples between 1927 and 1928. The short run underscores how quickly the company's executive range evolved, as newer chassis absorbed the role the 300/320 had been meant to fill.

1 distinct series across 1927–1928 — each identified by its chassis and engine numbers from period factory data.
| Malli | Mallivuodet | Valmistettu | Alusta | Moottori | Vaihteisto | Yhteensä |
|---|---|---|---|---|---|---|
| 12/55 hp Type 320 | 1927–1928 | 1927–1928 | 04 | 04 | 202 |
* Julkaistu tuotantoluku kattaa kyseisen mallin kaikki sarjat; lähde ei erittele sitä tarkemmin.


The M04 as fitted to the W04.
56 PS
41 kW · 55 hv / 3,200 r/min
162 N·m
119 lb·ft / 1,200 r/min