This article intends to document the design changes that Citroën had to make to import the SM into the USA and Canada. It is noted that in the early 1970's, Canadian authorities started ramping up their automotive safety and emission rules. The result was that the first SM's in Canada had some traits akin to the European models, but by 1973, they were nearly identical to USA cars.
On the DS model, US and Canadian DS's were nearly identical by mid-1971.
On DS’s, there was a pretty solid relationship between the car’s production date and the model year. A manufacturing date between 01 September and 31 August represented the model year. For example, a 1972 car could have been manufactured anytime between 01 September 1971, and 31 August 1972. Many design changes, both large and small, tended to be implemented in September to align with the next model year. We suspect that one of the reasons for this August/September change-over is that the factories were largely closed down in August, as per French custom. This allowed the factory to be mostly idle while they prepared for changes to the next year’s models.
The SM followed this same convention, although there were plenty of mid-year changes as well. As an example, two 1972 SM’s might have a number of visible and invisible differences. Much of this is documented in the parts books or other paperwork. But there are sometimes differences between two SM’s that do not appear to be specified in any documentation that we have access to. We have therefore relied on several experts to help confirm the configurations. These include (listed alphabetically:
Chris Dubuque, George Dyke, Roland Faragher-Horwell, David Hume, and Greg Long. Many thanks to Greg Long for letting us crawl over his many SM's for this article.
If any readers see any errors or omissions, please let us know.
PRODUCTION VOLUME FOR NORTH AMERICA
Depending on where you look, the number of SM’s sold in the USA and Canada varies a bit. For example, Wikipedia and Citroen-SM.org show slightly different tabulations. Based on our review, the production numbers from the Citroen-SM.org website seem more believable than the numbers from Wikipedia. The Citroen-SM.org numbers are repeated below:
One source indicates that of the ~2107 SM’s sold in North America, Canada received about 396 of them.
THE “AC” DATA PLATE
All USA DS models had a data plate that contained the model year (for example, a 1971 car would have a plate that said, “AC 71”). This plate was installed under one of the screws (or rivets) that held the serial number plate onto the frame, in the engine compartment.
USA or Canadian SM’s only sporadically have this AC plate. An example of a USA SM that has this plate is shown in the photo. It is not clear why some SM’s do not have this plate.
Euro SM's never received this plate.
POD-MOUNTED SERIAL NUMBER PLATE
All USA and Canadian SM’s had a small aluminum plate with the car’s serial number (VIN number) riveted on the left side of the steering wheel pod. A similar plate was added to the steering pod on USA DS’s, starting in mid-1969.
Euro SM's did not have this plate.