Drivers in long-term relationships with their cars

As a greater percentage of car and truck buyers take out longer auto loans, a new report shows Americans are holding onto their vehicles longer.

Experian Automotive analyzed the sale of more than 1.1 million vehicles in the first quarter of 2014 and found the average length of initial ownership was seven years and nine months. That's an increase of three months compared to the first quarter of 2012.

2014 Dodge Durango
Source: Chrysler
2014 Dodge Durango

"I'm not surprised people are holding onto their vehicles longer," said Brad Smith, director of automotive market statistics at Experian. "With buyers taking out longer auto loans, it's taking longer for people to reach positive equity in their vehicle, so many people are staying in their current vehicles longer."

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Higher-quality vehicles and their improved reliability—despite a seemingly never-ending lineup of recall announcements—are also contributing to the trend.

"People are no longer worried about being stranded in an old car that breaks down," Smith said.

October auto sales winners
October auto sales winners   

Americans who buy nonluxury American models are, on average, holding onto their cars and trucks longer, according to Experian.

For example, the typical Dodge is owned for nine years and five months. Buick buyers held onto their vehicles for almost the same length of time. The two brands topped the survey in regards to length of ownership.

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By comparison, Experian's study found those who bought a new Mercedes-Benz sold or traded in that model after six years and three months; BMW owners drove their vehicles for just more than six years.

"Many of those who buy luxury cars or SUVs are leasing them for three or four years, so luxury brands typically have shorter lengths of ownership," Smith said.

The study also found that the longer a driver holds onto their car, the lower the likelihood that their next vehicle will be from the same brand.

That's due, in part, to the fact that the longer someone has owned a car, the less likely they are to take it to the dealer for service and maintain a strong relationship with the brand, Smith said.

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Whether or not a vehicle is leased is another factor.

"Leases with their fixed-length ownership cycle are typically strong contributors to brand loyalty," Smith said.

Questions? Comments? BehindTheWheel@cnbc.com.