Usually from what I understand it's almost always Equifax. However, the dealership might pull from whatever your state/part of the country/worst credit report is. Here in Cali, Chrysler usually pulls Equifax and the dealership pulls Experian.
Here in TX they have always pulled TU (3 times) They also use some variation on FICO which gives more weight to previous auto finance - last year I wanted the 0% which they required 680 for - I checked my score with FICO.com and it was about 665 - when checked it an hour later theirs came back at 692! Neil
