December auto sales were strong compared to the rest of the year, reports TrueCar.com, which will lead to an estimated 13.5 million vehicles sold for the year on the whole.

The industry will reportedly announce figures of 1.2 million cars in total sold in December, which is up nearly 25 percent compared to November and 8 percent over the same month last year. In total, the industry is expected to sell approximately 1 million more cars than last year when the final figures are tallied.

"December's sales rate was a continuation of the rather slow and steady recovery that now symbolizes 2011," said Jesse Toprak, vice president of industry trends for TrueCar.com. "This year was absent of a blockbuster sales month but we see this pace of growth as healthy and sustainable in the coming year where the industry is going to sell nearly 14 million units based on the merits of its products and improved economy."

Whether you bought a new car this year or plan to hold out for 2012, it's important to invest in auto maintenance. Even if your current car is on its last legs, you'll be able to fetch a higher trade-in price for the vehicle if it doesn't require any car repairs.