Wann, who owned an accounting business, was astonished to find out RAFE was charging the same car loan interest rates to members who had good credit and bad credit. She said she didn't think that was fair and she knew that car loan companies were charging rates as high as 30% or more for customers with poor credit scores.

Much to the chagrin of federal regulators, Wann began charging subprime rates that were lower than car finance companies and other competitors.

"Private industry wasn't pricing their loans the way RAFE did 20 years ago, so I just started doing it because my task was to save the credit union," she recalled. "It took a long time to get it into shape."

As of June 30, RAFE was No. 1 on the top 20 list with a net interest margin rate of 9.58% and a return on asset ratio of 1.24%.

The credit union charges 16.22% on a used car loan and 14.71% on a new car loan, according to Wann. RAFE provides members with an incentive to pay their loans on time by knocking down their interest rate by 1% if they pay on time for one year during the term of the loan, she said.

Though its net interest margin was the highest in the land as of June, RAFE's rate of delinquent loans at 4.47%, and its net charge-off rate of 4.05%, were substantially higher than the peer averages of 1.28% and 0.45%, respectively. That, in turn, drives up RAFE's net operating expense, which was at 6.11%, and was significantly higher than the peer average of 2.86%.

These higher than peer average metrics and other factors required Wann to closely monitor the credit union's financials.

"Even though you have very good employees, anyone can get you into a lot of trouble if you don't keep a very close eye on everything monthly from loans to collections," she said. "That's why I regularly review a lot of reporting that tells me exactly what's going on."

Bill Wade, president/CEO of the $90 million Suntide Credit Union in Corpus Christi, Texas, may be one of the few who thought the Great Recession was a lucky event.

"We were very fortunate when the recession hit," Wade said. "A lot of financial institutions backed out of the auto market and so we had a tremendous amount of demand. We had pretty much all the loans we could bank and most of those loans were in the subprime area."

When he took over as CEO of Suntide at the end of 2007, he beefed up the credit union's operations by hiring more employees to handle the subprime loan process.

"We have six people in our collections department, and for a $90 million credit union, that is huge," he said. "A lot of credit unions our size have maybe one or two people in collections."

Since 2008, Suntide has increased its assets by about 20% annually. It is ranked No. 6 on the CU Times Top 20 list with a net margin rate of 6.69% and an ROA of 0.33%. The credit union charges 12.90% interest on used and new car loans, according to Wade.

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However, Suntide's delinquency rate was 2.16%, compared to peer average of 1.08% and its net charge offs are 1.94% compared to peer average of 0.46% as of June 2014. Its net operating expense rate was substantially higher at 5.23%, compared to its peer average of 2.85%.

"We spend a lot of face-to-face time with members and use a hard close," Wade said, meaning, employees ask members to make a convincing argument they are going to repay the loan.

"We have people with incomes well over $100,000 a year that have credit scores in the 500s," he said. "If you have a relationship with them, then they will pay you but they don't pay everybody. The bad thing about that is they are not afraid if you destroy their credit score if they don't pay because it's already gone. That's why we spend a lot of time with the members building that relationship so that we feel like they will pay us even if they don't pay somebody else."

Wade also devoted a lot of his time monitoring operations and finances. In 2013, he noticed some members were jumping to competitors that were offering mortgages.

"Once people got their mortgage there, they tended to move all of their other loans as well," he said.

To keep members from leaving, Suntide launched mortgage lending and currently has more than 60 loans on the books, according to Wade.

Melanie Kennedy, president/CEO of the $46 million Southwest Financial Federal Credit Union in Dallas, also focused on developing relationships with members who were mostly minimum wage workers living paycheck to paycheck with less than stellar credit scores.

"If you saw our members only on paper, then you may not want to do business with them," Kennedy said. "But because they have a relationship with us, we tend to overlook some of that."

Southwest Financial is ranked ninth on the CU Times Top 20 list with a net interest margin of 6.27% and an ROA of 1.28% as of June 30.

Kennedy said she's spearheading a sales and service culture to build up its book of business with members, which appears to be working. In 2013, Southwest Financial posted a 23% increase in loan growth and a 10% increase in loans as of June this year, she added.

The credit union charges an interest rate of 7.72% for used cars and 9.06% for new autos, according to Kennedy.

To manage delinquencies, Southwest Financial was successful in getting up to 90% of its borrowers to sign up for automatic payment of their loans from their direct deposit paychecks.

"Members like the automatic payments because it helps them with their budgeting and they tend to do it with other loans as well," she explained. "It also helps to establish that relationship, and we continue to grow that over time."

Southwest Financial's delinquency rate of 1.51% was only slightly higher than its peer average of 1.28%, according to NCUA financial performance reports for June 2014. However, the credit union's net charge-offs were substantially higher at 3.03% compared to its peer average of 0.45%.