Growing Number of Automatic Transmission Speeds

In case you didn’t catch it, the New York Times auto section recently had an interesting article on how the number of speeds in the automatic transmission has increased over the years. In the 1980s four speed gearboxes were the norm, which increased to five and six speeds in the 1990s, to more recently Chrysler planning to offer a 9 speed automatic starting in 2013.

The article explains how more stringent fuel efficiency regulations are increasingly driving up the number of speeds being introduced into automatic transmissions and why, for example, the Ford Fiesta and the Chevy Sonic (previously reviewed by RedlineNorth) have the same fuel efficiency as the larger Ford Focus and the Chevy Cruze (hint: it’s a function of available space).

It’s important to note that a lot of efficiency can still be squeezed out of the existing internal combustion engine. This opportunity is one of the main arguments that some auto manufacturers use when explaining why they have not developed their own electric vehicle or other alternative fuel models. Of course, the efficiencies derived from engine improvements can get applied in a variety of ways from increasing the horsepower and weight of the vehicle, to increasing its fuel efficiency, and usually in that order.

One could argue it is only when manufacturers are given an ‘incentive’ to increase fuel efficiency, such as through regulations, that the benefits of engine improvements get applied to overall vehicle fuel efficiency. It’s never that simply however.

The Times article also touches upon the immense amount of research and development required to develop new transmissions and how automakers are trying to reduce, or share, their investment and risk in transmission development through joint partnerships, such as between GM and Ford.  What seems certain is that more and more passenger vehicles will enter the market in the near future with an increasing number of transmission speeds.

The following infographic from the New York Times article provides a good overview how the number of gears has increased over time.

Increasing number of gears (Source: New York Times)

Sources: New York Times, Reuters Canada, US DOE, Car and Driver and egm CarTech