SAN FRANCISCO (AFX) -- Automotive supplier Dana Corp., whose shares have lost more than half their value during the past two sessions, threw its U.S. operations into voluntary Chapter 11 bankruptcy protection Friday, conceding that they were no longer able to meet financial commitments.

The announcement comes shortly after the company said that it had missed some $21 million in debt payments, which triggered a sell-off in the shares Thursday.

Dana said that it hopes to use the bankruptcy process to reshape its finances and operations. Its top executive pledged in a statement that his company 'is open for business as usual.'

The company would not detail how much of its business comes from its U.S. operations. According to a 2004 annual report, more than half of the firm's sales came from the U.S.

On Friday, stock in the Toledo, Ohio-based company was halted on the New York Stock Exchange at 69 cents, down 34% in the session.

Subsidiaries in Canada and Mexico, as well as overseas in Asia, Europe and South America are not part of the filing in the U.S. Bankruptcy Court for the Southern District of New York.

'Its bankruptcy will clearly take a minimum of 2 years given its complexity and the number of things they have to address while in bankruptcy,' said Howard Seife, a bankruptcy partner at Chadbourne&Parke LLP.

Financing for Dana's turnaround attempt will come from a $1.45 billion facility from Citigroup, Bank of America and J.P. Morgan Chase.

The company said that it has assets of $7.9 billion and liabilities of $4.7 billion.

Standard&Poor's cut Dana Corp.'s corporate credit ratings to D after the filing.

The filing was not unexpected, according to Prudential Equity Group analysts, who suspended their rating and price targets on the firm Friday.

With Ford Motor Co. and General Motors Corp. under increasing financial pressure because of slipping market share and rising costs, their suppliers have suffered. Delphi Corp. , which counts former parent GM as its biggest customer, filed for bankruptcy last year.

According to a Dana 2004 annual filing with the Securities and Exchange Commission, the company had 25% of its total sales from Ford. GM accounted for 11% in 2004, according to the filing.

Elsewhere in the industry, the effects of Dana's filing will be felt.

'These bankruptcies clearly have ripple effects,' said Seife. 'The second or third tier manufacturers that supply Dana will feel the squeeze as well because Dana will put enormous pressure on them with prices.'

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