Jamie Dimon is sounding the alarm on auto loans.

"Auto is clearly a little stretched, in my opinion," the JPMorgan Chase CEO said Thursday morning, speaking at the AllianceBernstein Strategic Decisions Conference in New York. "Someone is going to get hurt. ... We don't do much of that."

But other lenders have.

The average size of new auto loans is rising, as is the average payment size, according to research from Experian released Thursday morning.