Joyeux 14 Juillet à tous! For this Bastille day and the 100th Anniversary of Citroën​, here’s an old shot of a rare six-cylinder Traction Avant.

Every year for Bastille day, the New York Citroën and Velosolex club hosts a French car (and motorcycle) rally through Manhattan starting at Grant’s Tomb and ending at FIAF / French Institute Alliance Française​ in New York.

Today marked the 20th running of this event, but this shot is from when the event was new. On this day in 2001, loads of Citroëns (and a handful of Peugeots and Velosolexes) turned out, but none were so rare as the Traction 15-Six.

Origins of the Traction

Citroën, in just over a decade, had become the 4th-largest automaker in the world when work on the Traction began – but developing the car, and expanding the factory to build it, bankrupted the company; leading to Michelin’s takeover at the tail end of 1934.

The car, however, was a tour de force – easily the most advanced mainstream (read: not exotic or hyper-expensive) car in the world at that time and for some time after.

On a visit to American manufacturer Budd (who had supplied Citroën’s body tooling since the early 1920s) in 1931, André Citroën saw a unibody, fwd, V8 prototype designed by Joseph Ledwinka and William Muller.

Muller and Ledwinka, a very distant relative of Tatra’s Hans Ledwinka, had been involved with a number of advanced front-drive projects including designing the ill-starred Ruxton.

Returning to France, he had his engineers, André Lefèbvre (formerly of Voisin) and Maurice Sainturat develop a similar (Similar, but definitely not identical) car.

Lefèbvre himself had also designed another front-drive prototype (for Voisin) and he and his team had their work cut out getting the car to function reliably and be built for a reasonable cost.

Making the Traction Happen

Getting the Traction built was a Herculean task – it was way outside of conventional thinking in many respects even if other Front-drive pioneers were already on the market. Ultimately, the Traction was appreciably more expensive than other cars in it’s power class, but it was also much more modern.

Citroën licensed Budd’s patents for the unibody structure, among other technical patents it had to license to make the car, including Chrysler’s “floating power” engine mounts.

Architect Flaminio Bertoni did the rakish styling, which looked like a swoopy, low-slung ’34 Ford and had few non-coachbuilt competitors for sleekness at the time. Before WW2 there were coupe, roadster, and three sedan bodies.

The Traction was also originally to have had an automatic transmission developed by Dimitri Sensaud de Levaud (a proto CVT as seen on de Lavaud’s own prototypes) and a V8. Even though those items were axed for cost or fragility, the production car was still ultra modern.

It had a low center of gravity and by the standards of 1934 was extremely rigid because of the unibody. It was light and controllable with front drive, hydraulic brakes, and a torsion bar suspension. Rack and pinion steering and hydraulic shocks were added in 1936.

It was arguably still modern (underneath) when production ended in 1957. All it lacked was power.

Traction Evolution

The very first Traction was the 32-hp 1.3L 7CV. Considered underpowered right out of the gate, the 7CV was upgraded to 1.5L (35hp) and 1.6L (36hp) within the first few months. It was still called the 7 even though the actual horsepower ratings for these larger engines were 9CV. In mid-1934 it was joined by the 11CV, with 46-hp from 1.9L.

They were modern OHV motors at the time and though these numbers are low to modern eyes, they were only slightly behind the market. The 11 was the most popular Traction and the main model after WW2.

But Michelin wanted to expand the appeal – so a 77-hp 2.8L straight six was added in 1938 (full production did not really occur until 1939) – the 15 Six. With the arrival of the war, only a few Tractions were actually built during hostilities, but the 11 and the 15-Six returned after the war.

The Six gave the Traction appreciably more speed, but required lengthening the nose, making the car front heavy. It was also expensive, which made it a rare choice, but with ongoing evolutionary changes it lasted into 1956.

The last ones were the 15-Six H – these cars were the first to use the famous hydropneumatic suspension, on the rear wheels only. Not wanting to repeat the early teething problems of the 7CV with the DS, Citroën used these cars as a production testbed for the system.

Just over 50K sixes were built, of more than 758,000 Traction Avants overall.