Mercedes-Benz
540 K Spezial-Coupé

Why it matters

Closed bodies were a small part of 540 K production: RM Sotheby's says just 42 of the 540 K cars in four years of production received closed coachwork, and only about seven of those were coupes. The Sindelfingen Spezial Coupe on chassis 130944 was chosen by Mercedes-Benz to represent its top model at the Paris Salon in October 1936. It was designed by Hermann Ahrens, whose Sonderwagen section was responsible for the limited-production bodies on the supercharged eight-cylinder chassis.

How rare is it?

Six separate kinds of rarity – never combined into one number.

Each kind of rarity is rated separately and never combined.

Production

Every figure says what it counts.

Independent counts (e.g. engine and colour) are never combined into a calculated figure. Surviving examples are never presented as original production.

History

The 540 K was officially launched at the Paris Motor Show in early October 1936. The RM Sotheby's catalogue says Mercedes-Benz selected a coupe as its show car at the Paris Salon in October 1936, an unusual choice because the great majority of 540 Ks were open cars. Mercedes-Benz delivery papers call the car a "Spezial Coupe", and a copy of the original build sheet records the first customer. Experts from Mercedes-Benz Classic inspected the car in 2011 and found the engine number (130944) matching, the body probably never removed and the transmission and steering of the correct series.

Earlier closed Sindelfingen designs include the coupe built for racing driver Rudolf Caracciola and the Autobahn-Kurier, a fastback five-window body suggested by Wilhelm Haspel in 1934 of which two were built on each of the 500 K and 540 K chassis, according to RM Sotheby's. A different type of 540 K coupe also exists: a 1937 Sindelfingen-bodied 540 K (chassis 154143) was rebuilt as a coupe by Hebmuller around 1951, who removed the convertible top and windscreen pillars and added a new roofline.

Technical specifications

Engine

Transmission & drivetrain

Chassis, body & dimensions

Performance

“Not yet verified” means no source has been checked for that value yet. Nothing is estimated to fill a gap.

Identification guide

How to tell an original from a replica or later conversion.

The Sindelfingen Spezial Coupe has sweeping front fenders that merge into small running boards and flare up into teardrop-shaped rear fenders, skirted rear wheels with a chrome emblem repeating the front centre-lock hub, a rounded roofline tapering into the rear deck, a stacked pair of spare wheels set almost flush in the deck and a transverse rear seat for one passenger. A chrome beltline follows the hood break and curves down across the door. Chassis and engine numbers should match (130944 on the Paris show car) and the factory papers call the car a "Spezial Coupe".

Beware of later conversions that imitate the look. The Hebmuller coupe on chassis 154143, made around 1951 from a Sindelfingen convertible, is described by RM Sotheby's as reminiscent of the factory Spezialcoupe, and it shows the sloped vee windscreen and altered rear of the rebuild rather than the factory body.

Sources

Each number links to the exact facts it supports.

1. 1
   RM Sotheby's Monterey 2011 – 1936 Mercedes-Benz 540 K Spezial Coupé by Sindelfingen Level B

   • 7 about seven coupés built on the 540 K chassis (per Jan Melin research)

   Accessed 2026-11-12
2. 2
   540 K / W 29, 1936 - 1939 Level A Mercedes-Benz Public Archive (Classic M@RS)

   • Engine type : M 24 II (Specifications)
   • Number of cylinders / arrangement : 8 / in line (Specifications)
   • Total displacement : 5401 cc (tax classification: 5363 cc) (Specifications)
   • Bore x Stroke : 88 x 111 mm (Specifications)
   • Compression ratio : 5.2; depending on fuel, up to 6.5 (Specifications)
   • Valve operation : 1 lateral camshaft; Camshaft drive : via spur gears (Specifications)
   • Fuel system : 1 twin updraught carburettor Mercedes-Benz (Specifications)
   • carburettor engine with engageable Roots supercharger (Specifications)
   • Rated output : 115 hp, with supercharger 180 hp at 3400 rpm (Specifications)
   • with supercharger 180 hp at 3400 rpm (Specifications)
   • Rated torque : 44 mkg at 2200 rpm (Specifications)
   • Gearing : 4-speed manual transmission; Availibility : up to 1938 (Specifications)
   • Gearing : 5-speed manual transmission; Availibility : from 02.1939 (Specifications)
   • Gear ratios : I. 3.90; II. 2.88; III. 1.45; IV. 1.0 (Specifications)
   • Final drive ratio : 3.08 or 3.60 (Specifications)
   • Driven wheels : rear wheels (Specifications)
   • Frame design : box-section pressed-steel low-bed frame (Specifications)
   • Front-wheel suspension : double wishbone; Front springs : coil springs (Specifications)
   • Rear-wheel suspension : swing axle, up to 1938 with additional compensating springs (Specifications)
   • Brake system (foot brake) : hydraulic, with Bosch-Dewandre vacuum booster (Specifications)
   • Steering : worm-and-nut steering (Specifications)
   • Wheelbase : 3290 mm (Specifications)
   • Maximum speed : 170 km/h (Specifications)
   • Fuel tank: position / capacity : in the rear / 110 l (Specifications)
   • Fuel consumption : 29 l (Specifications)

   Accessed 2026-11-12