My guess is that they are slow pays, rolling 30 day lates every month. That is what happened to me, I made my payment monthly but always behind 30 days. This went on for like 2 years.

My last late was in May 2011 and I bought a new car that summer. Interest rate was like 16 percent.

I had a crap load of inquires too.

Then later that fall I bought a second car, score was better and got a good rate. Had about 70k total in auto loans with the second car. But the bank required my Wife be on the loan too because they wouldn't give me 2 auto loans.