Vehicle sales for the month declined 5.5% year-over-year to 48,380 units from 51,205 units, truck sales also decreased 1.0% to 110,788 units, while SUVs sales rose 8.0% to 82,881 units as compared to a year earlier.
Mustafa Mohatarem, GM's chief economist, forecasts 2018 total vehicle sales (including medium and heavy trucks) to exceed 17 million units for the fourth year in a row.
According to Autodata, 2017 full-year sales struck 17.23 million units, down nearly 2 percent from an all-time US record of 17.55 million units in 2016. Fiat Chrysler reported a decline of 8 percent compared with 2016.
Honda's United States sales rose 0.2% for the year to 1.6 million.
General Motors was the top seller but had a drop of 1.4 percent. Fiat brand sales fell 33 percent, while Ram slipped 3 percent, but still sold 44,907 pickup trucks.
The migration of consumers to larger, more expensive vehicles, especially luxury pickup trucks and crossovers, has come as easier credit and longer auto loans have enabled people to buy or lease vehicles they might have once considered unaffordable.More news: S/Africa: ANC body must act decisively on Zuma's future - Veterans
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Toyota Canada recorded its best sales year ever in 2017, bolstered by record hybrid, truck and Lexus vehicle sales.
Total monthly sales compare to an estimate of 232,000 by analysts Kelley Blue Book (KBB), who also estimated an average transaction price of $40,421, up 2.5% year over year and up 1% compared with November's average selling price of $40,023.
"In 2017, we had solid GDP growth and good news on employment, wages and consumer sentiment, which helped deliver very strong retail sales for the auto industry", he said. But most other automakers saw declines.
Ford's sales fell 1.1 percent to 2.6 million for the year compared to 2016, but it reported a surprise increase in December 2017 sales, fueled in part by the continued success of the F-Series pickups and other large vehicles. GM reported a less dramatic monthly drop than analysts expected, as sales of the Chevrolet Silverado climbed 25%. SUV sales fell 12% year over year in December. Ford saw a decline of 0.9 percent, and Toyota was down 0.6 percent. Fiat Chrysler's sales fell 11 percent, while Toyota's sales dropped 8 percent and Nissan's sales were down 9.5 percent.
"Average transaction prices closed the year on a strong note, rising almost 2% in December 2017 to set a record high", said Tim Fleming, analyst for Kelley Blue Book.