Citroën is celebrating the 40th anniversary of the CX. Designed to replace the iconic DS, the CX served as Citroën’s flagship from its launch in 1974 until the arrival of the XM in 1989.

Citroën started seriously developing a successor to the DS in the late 1960s. In 1972, the company built a sleek prototype called Project L (pictured below) that accurately previewed the CX’s overall silhouette, though it was still far from the final design. When launched, the CX featured a highly-aerodynamic look that was penned by Robert Opron, the same designer that drew the GS and the SM. Notably, the CX was shorter than the DS it was tasked with replacing and it was equipped with an innovative concave rear window that eliminated the need for a wiper.

From the earliest days of the project, Citroën designed the CX to use Wankel rotary engines developed and built by Comotor, a joint-venture the automaker founded with NSU in the late 1960s. Period reports indicate the range-topping CX was initially set to feature a triple-rotor 1.5-liter Wankel rated at 160 horsepower, while lesser models should have been powered by a small twin-rotor 0.9-liter engine tuned to generate 110 horsepower. Citroën also planned on selling the CX with several carbureted four-cylinder mill sourced from the DS and at least one diesel, but, clearly, the bulk of the high-end models should have been Wankel-powered. This is a very important part of the CX’s development story: Wankel engines are highly compact so the engine bay was designed to fit nothing larger than a four-cylinder.

Unfortunately for Citroën, introducing a large sedan powered by a Wankel engine became almost literally impossible for a number of reasons. First off, rotary engines used more gasoline than traditional piston engines and the oil crisis that hit in 1973 sent gas prices sky-rocketing. Second, rotary engines faced a number of important mechanical issues that sometimes led to premature engine failure, a tendency that was flawlessly demonstrated by the NSU Ro80. Finally, a lot of buyers were simply hesitant to become early adopters of what was a relatively unknown technology. Citroën tested the market in 1973 with the GS Birotor, a total flop that was pulled from the market after less than 1,000 examples were built.

Citroën backpedaled and canceled all Wankel-powered variants of the CX with mere months to go before the car was scheduled to debut. Engineers panicked and experimented with a variety of solutions including fitting the CX with the SM’s potent Maserati-designed V6 engine. Surprisingly, the six-cylinder could apparently be shoe-horned transversally into the CX’s engine bay but the project was ditched because it was too tight of a fit. Executives brought up the idea of making the engine bay larger but the idea was also ruled out because it was far too late in the car’s development to make structural modifications. Delaying the CX was not an option because the DS was getting close to its 20th birthday and the company was in dire financial straits.

When all was said and done, the CX lineup was introduced to the press and the public in August of 1974 with two models: The CX 2000 and the CX 2200. The 2000 had a 102-horsepower 2.0-liter four, while the 2200 was equipped with a 2.2-liter rated at 112 horsepower. Both engines were carried over from the DS with only minor modifications.

In early CXs, power was sent to the front wheels via a four-speed manual transmission, though a five-speed unit and an automatic gearbox were both made available later in the production run. Following the path blazed by the DS, all CXs were equipped with a hydraulic suspension setup that provided a level of comfort and stability that was second to none.

The CX won the prestigious European Car of the Year award in 1975, beating the first-generation Volkswagen Golf by a long shot and the Audi 50. The Wankel issues hadn’t impeded the CX’s success but the entire Comotor fiasco played a sizable role in pushing Citroën towards its second bankruptcy. The firm was later taken over by Peugeot, making the CX the last sedan designed entirely by Citroën. The very last Citroën designed in-house was the Axel hatchback, which was largely developed in the early 1970s but kept on the backburner until it was launched seemingly as an afterthought in the mid-1980s.

CX sales exceeded expectations in 1975, and the lineup grew with the addition of the CX Super, the CX Pallas, the long-wheelbase CX 2400 Prestige and the diesel-powered 2200D, the latter being Citroën’s first post-war diesel-burning car. A long-wheelbase station wagon with a raised roof was introduced the following year to replace the DS wagon.

Citroën made several mechanical and aesthetic updates to the CX over the course of its long production run. A facelifted model (sometimes called mk2 or series 2) launched in 1985 brought modifications such as plastic bumpers on both ends, a more modern-looking radiator grille, an all-new interior, new alloy wheel designs and plastic hubcaps. Facelift cars benefited from a Peugeot-sourced 2.0-liter four-cylinder engine that was also found under the hood of the Renault 20 TS and select versions of the Peugeot 505.

To boost sales, Citroën expanded the CX lineup downwards with the addition of the Leader model (a trim level also available on the BX and the Visa) and upwards with performance-focused GTI-badged variants capable of comfortably keeping up with Mercedes and BMWs on the German Autobahn.

150,000 CXs were built in 1978, the model’s best year. The millionth example rolled off the assembly line on October 30th, 1987, but the end was near as Citroën was busily developing the XM. Interestingly, a handful of CXs were fitted with a primitive version of the XM’s electronic Hydractive suspension and put in the hands of carefully-selected customers in order to gather data on how well the system worked and what kinks still needed to be ironed out.

CX production ended in 1991 when the last station wagon (which was re-christened CX Evasion) was built in Aulnay-Sous-Bois, on the outskirts of Paris. All told, Citroën built 1,041,560 CX sedans and 128,185 station wagons over a 17-year period. Happy 40th, Citroën CX!

The CX worldwide

Citroën left the United States in the middle of the 1970s so the CX was never officially sold there. However, a New Jersey-based company called CX Automotive (CXA in short) imported a number of gray market models in the 1980s and early 1990s. The cars were sold in a handful of states but they were not available in California because they did not meet the state’s strict emissions regulations.

Like we mentioned last April, Citroën sent 2,500 CXs to China in 1984 in hopes of being awarded a lucrative contract to provide the country with a large car. The contract was awarded to Volkswagen, and very few of the CXs shipped to China are still around today.

All photos courtesy of Citroën’s archives department except for the Project L photos which were taken by Ran When Parked.