Washington, D.C. ? Auto lender GMAC Financial Services will receive $7.5 billion in additional government aid to keep loans flowing to would-be buyers of GM and Chrysler vehicles and shore up its capital position — marking the second time the government has stepped in to prop up the lender.

To help GMAC raise additional funds, the Federal Deposit Insurance Corp. took the rare step Thursday of allowing the junk-rated company to gain access to its debt guarantee program.

GMAC will be allowed to issue as much as $7.4 billion in debt, guaranteed by the FDIC in case the company defaults on payment.

In addition, the Federal Reserve waived rules to give GMAC’s new bank, called Ally Bank, more leeway to make loans to GM customers.