By Shawn Langlois

SAN FRANCISCO (Dow Jones) - GMAC Financial Services on Tuesday said it lost $675 million in the first quarter, a bigger loss than a year ago as General Motors Corp.'s top lender was bogged down by credit woes in the auto and housing markets.

GMAC reported a loss of $589 million in the first quarter a year earlier.

"The effects of a soft economy and weaker credit performance on legacy assets continued to put pressure on GMAC's financial performance in the quarter," Chief Executive Alvaro de Molina said in a statement.

He added that there were signs of progress in retail auto-lending, wholesale financing and the prime jumbo mortgage market.

New vehicle financing, while improving from the fourth quarter, plunged to $3.4 billion from $13.1 billion in the first quarter of 2008 - not surprising in light of the dismal car sales results, particularly from GM (GM).

The once-lucrative mortgage business posted a loss of $125 million, vs. a loss of $859 million a year ago. The most recent quarter included a one-time gain of about $900 million from the company taking debt off its books.

New loans fell from a year ago but refinancing has picked up amid lower interest rates and margins have improved thanks to more government business.

GMAC said its consolidated cash and cash equivalents fell to $13.3 billion as of March 31 from $15.2 billion at the end of 2008. Total assets rose to $36.4 billion from $32.9 billion at the end of last year helped by an increase in deposits.

GMAC, which received billions of dollars from the U.S. Treasury as it became a bank holding company, said it should garner benefit with additional business thanks to its recent deal to assume Chrysler Financial's new car loan business.

"This agreement leverages GMAC's strengths, diversifies our auto finance business and provides new revenue opportunities for the company," de Molina said.