Image: Couple shopping for a new car © Tetra Images, Getty Images

As more Americans head to dealerships to buy a new car or truck, they are increasingly stretching out their auto loans to at least five years -- and often to six or seven.

That's one finding in the latest report by Experian, which analyzed auto loans written in the second quarter of 2012. Experian said the average monthly payments for both new and used vehicles bought in the second quarter went up, while the average credit score dropped to its lowest level since early 2008.

Overall, the report shows the size and scope of the expansion in the auto loan market, fueled by greater credit availability and more consumers looking to buy.

Spreading out auto loans

Experian says the average duration of a new-car loan climbed by a month in the second quarter, and now stands at 64 months. The fact that the average auto loan now stretches out to 5.3 years isn't surprising when you see the shift in loan length:

  • 4-5 years: Down 19.6%
  • 5-6 years: Up 7.6%
  • 6-7 years: Up 26.4%

How popular are longer auto loans? Experian says that 58% of all new-vehicle loans stretch over five years or longer. This is just the latest indication that the days of three- to four-year auto loans as the standard for financing a new car are long gone. In fact, Experian says that only around 10% of auto loans are now for four years or less.

Monthly payments creep higher

Continuing an ongoing trend, the average monthly payment also edged slightly higher in the second quarter.

Experian found that the average new-car loan monthly payment was $452 in the second quarter, up $2 from a year ago. The average monthly used-car loan payment rose $4 to $351.

In both cases, monthly payments are rising in large part because car and truck buyers are financing more. The average amount financed with a new-vehicle loan was $25,714, an increase of $474 from last year, according to Experian. For a used-vehicle buyer, the average amount financed was $17,433, an increase of $370.

Experian also reported that the average credit scores for new- and used-car buyers both edged lower in the second quarter as credit became easier to find and dealers wrote more loans to those with less-than-pristine credit records.

The average credit score for a new-vehicle buyer was 753, according to Experian. That's nine points lower than a year ago and the lowest score since the second quarter of 2008. The average credit score for a used-car buyer also dropped nine points, to 662.

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