Over the last several years, it's been a three-way horse race for the world's biggest automaker by volume. For decades, General Motors was the undisputed sales king. Then in 2008, Toyota obliterated the traditional pecking order by outselling GM. The 2011 earthquake and tsunami took a toll on Toyota's supply chain and global production, but the company worked hard to regain its lost momentum and came out on top one again for 2012, with global unit sales of 9.75 million, according to Bloomberg. GM sales totaled 9.29 million, and Volkswagen took third place with 9.07 million.

Despite weak markets in Europe and a sales decline in China attributed to public sentiment surrounding a territorial dispute between China and Japan, Toyota surged to the top largely on strength in the U.S. and Japanese markets, which increased the company's total U.S. market share to 14.4 percent, up from 12.9 in 2011. Home-market sales in Japan increased significantly by 35 percent, totaling 2.41 million units.

The 2014 Toyota Tundra is expected to be revealed at next week's Chicago auto show. While never a serious threat to the Ford F-Series or Chevrolet Silverado in overall sales, the 2014 model will be the first major redesign since the second-generation Tundra's debut in 2007, signaling a potentially strong 2013 calendar sales year for Toyota in the U.S.

Source: Bloomberg