DETROIT (AP) -- If your credit isn't good, General Motors Co. still wants to sell you a car.

The problem is, it can't. At least not in big numbers. That's why the automaker wants more control over its lending again.

GM's top North American executive Mark Reuss, under pressure to quickly sell more cars and boost GM's value as it gets ready to sell stock to the public, said a shortage of subprime lending is holding back sales in the U.S.

But the automaker's main lender, Ally Financial Inc., has little appetite for risky loans, having spent the last few years cleaning up its own financial mess caused mainly by its failing mortgage lending business. Both companies are majority-owned by the U.S. government.

For decades, GM owned Ally, writing its own loans through the so-called captive finance arm. Nearly every automaker makes loans in such a fashion. But a cash-starved GM sold most of Ally -- formerly known as GMAC -- in 2006.

GM and Ally now have a loose partnership that gives Ally control over who gets a car loan. If GM returned to auto lending -- either through buying Ally's auto business or starting its own in-house lending unit -- it could set lending standards itself. That could benefit the automaker by allowing it to extend loans to people with weaker credit and to more lease customers.

"There's a real sense of urgency on GM's part to maximize its sales" as it gets closer to the stock offering, said Kirk Ludtke, senior vice president of CRT Capital Group in Stamford, Conn.

Subprime buyers make up a significant portion of the car buying market. About 16 percent of all new-vehicle loans written in the fourth quarter of 2009 were to customers with below prime credit, according to credit agency Experian. That means they went to customers with credit scores below 620 on a 300-to-850-point scale.

Reuss, president of GM North America, would not say outright if the automaker was looking to set up its own financing operation. But he said last week that one need only to look at auto loan data to find plenty of good reasons for GM to have control of its own financing.

For example, Honda Motor Co. gets 20 percent of its sales and leases from subprime buyers, he said. GM, on the other hand, gets only 1 percent because it can't access the money to loan to those customers.

"They're able to finance their cars at a much lower level than we are," Reuss said. "I'm not sure what the answer is. But it would sure help my sales, the company's sales in North America, if we were able to get access."

During the recession, lending to subprime customers tumbled as the credit markets froze and delinquencies spiked. Leasing also ground to a halt as the resale values of cars plunged.

Ally has been less than eager to resume lending to risky customers. After GM sold a majority stake in Ally, the lender became heavily involved in the subprime mortgage boom, a move that nearly bankrupted the company when the housing market collapsed. Ultimately, the federal government has spent $16.3 billion to bail out the lender, leaving taxpayers with a 56 percent stake in the former GMAC.

Ally has spent the last year trying to clean up its mess, diversifying its customer base beyond just GM buyers, launching a highly profitable online banking service and working to sell what remains of its mortgage lending business. Earlier in May, the company posted its first quarterly profit in more than a year and rebranded itself as Ally.

Subprime lending for cars is generally considered less risky than mortgages. During the recession, borrowers didn't default on car loans as much as they did on homes because the value of cars never became overinflated. Also, if a car buyer defaults, the lender can quickly repossess the vehicle and resell it, recouping at least part of the lender's investment.

Ally would appear to have little to gain, though, from selling its auto lending operation, by far its most profitable line of business. Writing auto loans made Ally $846 million in pretax profit in the first quarter -- the division's fifth straight quarterly profit -- up 28 percent from a year earlier.

Competition from a new GM-owned lender also would be tough. In the first quarter, Ally wrote 34 percent of all loans to GM buyers, a figure that has been rising over the last year. It handled 88 percent of the loans that finance GM dealers' inventory.

An additional complication comes from Chrysler Group LLC, which also depends on Ally for loans. CEO Sergio Marchionne told reporters Thursday that Chrysler could be at a disadvantage if GM buys back part of Ally. "If they control the lending practices and the degree of penetration and support that they gave to Chrysler, that would make us very, very concerned," he said.

In the end, any decision is likely to be influenced by the Treasury Department, which designated Ally the preferred lender for Chrysler as well as GM -- and owns big stakes in all three after bailing them out last year.

Ally, for its part, issued a statement last week saying the company is committed to staying in the auto lending business. Ally spokeswoman Gina Proia declined to comment on whether the lender has faced pressure from GM to make more subprime loans or leases. However, she said that as the economy has improved, Ally has been opening its pockets to more customers.

For example, 12 percent of all auto loans that Ally wrote in the first quarter were leases, up from 4 percent in the fourth quarter and virtually zero last year, she said.

"As the financial crisis has eased and as the credit markets come back we have been able to broaden our offerings and look at the credit spectrum more broadly," Proia said. The company does not disclose the percentage of loans it makes to subprime customers, she said.

GM's Reuss said Ally has been a good partner and has given the automaker everything it has asked for -- including a recent 24-month lease deal. Ally also has been helpful in targeting competitors or regions with loans.

He said GM hasn't asked Ally about expanding subprime lending, and he said the two companies might be able to work out a deal.

"They do a good job. But clearly there's some opportunities there, too," he said.