Banco Santander (SAN
) mulls an IPO of its U.S. auto-finance unit
, not long after it raised $4B by peeling off a slice of its Mexican business in an IPO. Santander has a book of about $18B in the U.S. and is seeking a valuation of at least $6B, according to sources. The bank is looking to sell high as it deals with troubles back home.