NEW YORK (TheStreet) -- Americans are holding onto their cars for longer, with the average automobile age in the country rising to an all-time high of 11.6 years old in 2016 from 11.1 years old in 2012, CNBC's Phil LeBeau reported on "Closing Bell" Tuesday afternoon.

This is a result of two trends, he said. First, cars are more reliable so car owners feel more confident about keeping them on the road for longer.

Second, the prices of new cars have gone up and buyers are spreading out their auto loans, LeBeau said. Since they're taking longer to pay off the automobile, new car owners are keeping their cars for an average of about seven years. 

Auto Parts Retailers are the biggest benefactors of this trend as people come in for things that need to be replaced on their older vehicles, he said. 

By 2021, 20 million vehicles in the U.S. will be at least 25 years old, showing that this is not a short-term shift.