Auto loan statistics are compiled by Equifax. Here’s a piece on Equifax’s October 2014 report.
http://insight.equifax.com/auto-market-revels-in-record-vehicle-loan-totals-a-breakdown-of-the-recent-national-consumer-credit-trends-report/
It shows that in the fall of 2014 financial institutions had 31.4 million auto loans worth $453 billion and auto companies had 34.1 million auto loans worth $471.2 billion.
Here’s an Equifax report on subprime auto loans.
http://www.equifax.com/assets/corp/subprime_auto_economic_commentary.pdf
