The U.S. is injecting another $3.8 billion into GMAC Financial Services to help cover mortgage losses, in a bailout that makes the government the majority owner of the auto and home finance company.

GMAC said after the capital infusion it does not expect to record more major losses from its mortgage lending unit, which should help stabilize results.

The company is one of the largest car loan makers in the United States, and earning profit will give it more capacity to make loans and eventually pay back the government.

Many analysts see GMAC's mortgage assets, which make up about a third of the company's $178.2 billion balance sheet, as the main obstacle to the lender reaching profitability.

Those assets have already forced GMAC to seek new funds. Before Wednesday's capital infusion, GMAC had already received $12.5 billion of aid from the United States.

A government test of the company's capital in May, known as the stress test, found that GMAC needed $11.5 billion of equity. About $9.1 billion of that equity had to be new capital, while the rest could come from converting existing capital into new instruments such as common equity.

GMAC has raised about $7.3 billion of that $9.1 billion of new capital from the United States. The government decided that the company has raised enough because the bankruptcy of General Motors , which once owned all of GMAC, had less of an impact on the finance company than previously expected.

NOT OUT OF THE WOODS YET

Questions still remain for GMAC, though. The extent of future losses from its mortgage assets is not yet clear, a bondholder said.

He added that the best route for GMAC to follow now would be to sell off GMAC's mortgage servicing business, which collects payments from borrowers and is worth more than $3 billion on the company's books.

The bondholder, who requested anonymity because he is not authorized to speak to the media, said the company could continue to make new home loans through its Ally Bank unit.

GMAC's remaining mortgage loans could be used to pay off coming debt obligations linked to its Residential Capital unit, the investor added. If the assets don't perform well enough, that unit could go into bankruptcy, he added.

GMAC said in its statement that its board of directors reviewed Residential Capital's options and decided unanimously to take the steps announced on Wednesday.

GM sold a 51 percent stake in GMAC to private equity firm Cerberus in 2006, but held onto 49 percent of the company. Over time, GM's stake has been whittled down to 16.6 percent, including a trust managed for GM's benefit. Cerberus' stake is now 14.9 percent. The U.S. now holds 56.3 percent, with the rest of the company being held by Cerberus investors.

The government previously held about 35 percent of the company's common stock.

GMAC's mortgage business lost nearly $600 million in the third quarter, but its auto finance operations were profitable, earning about $164 million after taxes.

In November, GMAC Chief Executive Al de Molina resigned and was replaced by Michael Carpenter, a board member and former Citigroup executive.

On news reports of the planned capital infusion, the cost to insure GMAC's debt against default in the credit derivatives market fell to around 4.4 percentage points, or $440,000 a year for five years, from 4.66 percentage points at Tuesday's close, according to market data company Markit.

(Additional reporting by Corbett B. Daly and Tim Ahmann in Washington, and Dan Wilchins and Karen Brettell in New York; Editing by Derek Caney, Dave Zimmerman and Steve Orlofsky)

Investment Citigroup