* $11.5 billion capital shortfall

* Fewer options than other lenders

By Jonathan Stempel

NEW YORK, May 7 (Reuters) - GMAC LLC, the auto and mortgage lender, will likely be forced to seek more taxpayer help in its effort to raise $11.5 billion of new capital following the government "stress test" of its balance sheet.

But unlike the nine other lenders that underwent similar tests and were deemed to require more capital -- only two of which, Bank of America Corp (BAC.N: Quote, Profile, Research) and Wells Fargo & Co (WFC.N: Quote, Profile, Research), need more than GMAC -- GMAC has few obvious ways to raise the sum it needs.

While it could convert preferred shares issued as part of a $6 billion federal bailout in December, that would get it only about halfway to the target. GMAC became a bank holding company in connection with that bailout and a debt restructuring.

The capital shortfall adds to problems for Detroit-based GMAC, which has lost money in six of the last seven quarters as mortgage and other credit losses soar, while sales volume falls at former parent General Motors Corp GM.N. It has three major operations: auto finance, mortgage lending and insurance.

"GMAC's first option is to get more money from the government," said Van Conway, the president and a turnaround expert at Conway, MacKenzie and Dunleavy in Birmingham, Michigan.

"If that fails, it may have to dispose of more profitable units, and that means insurance," he added. "But if GMAC were to sell businesses, given market conditions, it would not be a good time."