The monthly auto payment is still No. 1 when distressed households have to pick which bill to pay, the latest payment study from TransUnion shows.

And that’s helping to keep auto delinquencies low. So low, in fact, that a TransUnion analyst is questioning whether auto lenders might be leaving some money on the table by staying conservative.

“The question with autos is: When you have the lowest historical delinquencies, when do they move back up to historical means? It could mean there’s opportunity being left behind,” said Steve Chaouki, TransUnion group vice president and co-author of the company’s “Payment Hierarchy Study” released Sept. 19.

“I mean, hypothetically, if you had zero delinquencies, if you’re a lender you’d have to ask yourself: ‘Could I be lending more?’” he told Automotive News in a phone interview.

On average, only 0.8 percent of auto loans were 60 or more days delinquent in the second quarter of 2013, a barely measurable increase from 0.79 percent a year earlier, TransUnion said last month. Loans that are 60-plus days delinquent are the most likely to be written off as a bad loan.

TransUnion reported in early 2012 that many households faithfully kept up their car payments during the recession even if they were in arrears on their mortgage.

That was a change from previous economic downturns during which households typically sacrificed other assets in order to keep up with the mortgage. Common wisdom is that in an era of high unemployment and economic uncertainty, consumers do everything they can to hang onto their cars to get to work or job interviews.

Chaouki said another factor affecting mortgages was that during the Great Recession, home prices fell and left many consumers so far upside down in their mortgages — owing more on their home than it was worth — they didn’t see the point in trying to keep the mortgage current.

Last week’s study shows auto payments remain a priority. What’s changed is that home prices have begun to recover. Mortgage delinquencies have declined at the same time, Chaouki said.

“The historical view is that the priorities were always mortgage, auto, credit cards, in that order. Then in the Great Recession, mortgages fell out of favor and auto became No. 1. Then it was auto, credit card, mortgage,” Chaouki said. “Now mortgage is making a move. It’s more or less in a dead heat with credit cards.”

Chaouki said it’s not necessarily bad for auto loans if mortgages eventually work their back to No. 1 in the list of household priorities.

“As delinquencies go up, it’s not necessarily a bad thing, as long as they go up according to expectations, to historical norms,” he said. “A simple rise in auto delinquencies is not something to be concerned about. It’s just that mortgages have gotten better faster.”

TransUnion said last week that delinquencies on mortgages fell 29 percent in 2012 compared with a decline of 6 percent for auto loans.

Said Chaouki: “In autos, the sky definitely is not falling.”