It created free trade in passenger cars, trucks, buses, tires and automotive parts between the two countries, greatly benefiting the large American car makers. In exchange the Big Three car makers agree that automobile production in Canada would not fall below 1964 levels and that for every five new cars sold in Canada three new ones would be made there.
Before the Auto-Pact the North American automobile industry was highly segregated. Because of tariffs only three percent of vehicles sold in Canada were made in the United States, most of the parts were manufactured in the U.S. and overall Canada was in a large trade deficit with the States in the automobile sector.
The Pact saw vast and immediate changes. Canada began to produce far fewer different models of cars, rather much larger plants producing only one model for all of North America were constructed. While in 1964 only seven percent of vehicles made in Canada were sent south of the border by 1968 this was sixty percent. By the same date forty percent of cars purchased in Canada were now made in the United States. Overall the agreement was of great benefit to Canadian workers and consumers. The more efficient market lowered prices and the increased production created thousands of jobs and wages rose to match those in the United States. Automobile and parts production quickly passed pulp and paper to become Canada's most important industry. The trade deficit has turned into a trade surplus worth billions of dollars annually to Canada.
At the same time there were important disadvantages to this arragement. It left the Canadian automobile industry firmly in the hands of American corporations. Unlike, for instance, Sweden with Volvo and Saab, Canada has no domestic car makers, despite a long history of Canadian car companies. The agreement also lead to the creation almost exclusively of blue collar jobs. Administration and research and development remained in the United States. The agreement also prevents Canada from pursuing free trade in automobiles with other nations, such as Japan. The growth has also been very regionally skewed with southern Ontario overwhelmingly being the main centre of production.
The act was modified by the 1988 Canadian-American Free Trade Agreement but still remains in force today. The deal can be repealed by either side with a years notice.