Last week, GM recalled almost 3 million vehicles globally and was fined a record $35 million by NHTSA. It also faces probes by the US Department of Justice, Congress, the Securities and Exchange Commission and several states for its handling of the faulty ignition switch, which engineers first discovered in 2001. GM has been criticized for not recalling the vehicles affected by the bad ignition switch before this year.

GM to pay $35m fine for delaying recalls

US probes GM recall linked to 13 deaths

Wednesday's two recalls bring the number of vehicles affected by its recalls this year to almost 13.8 million in the United States. That tops the previous full-year high of 10.7 million vehicles that the company recalled in the US market in 2004. It pushes the number of vehicles that GM has recalled globally this year to more than 15.8 million.

GM took a $1.3 billion charge in the first quarter for recall-repair costs and said Tuesday that it expects to take another $400 million charge in the second quarter for the same reason.

Since the recall began in February, GM has been hit with more than 70 lawsuits from customers who say their cars lost value because of the ignition defect, according to court documents.

Two US senators on Tuesday introduced legislation that would require federal judges to consider the public's interest before granting requests to seal court records in cases that have an impact on public health and safety.

Democratic Senator Richard Blumenthal of Connecticut and Republican Senator Lindsey Graham of South Carolina offered the bill in response to the GM ignition switch recall. GM has reached confidential settlements in several lawsuits brought by families of victims of accidents that have been linked to the ignition defect.

"GM's recent legal maneuvering reaching secret settlements shows why this legislation is essential," Blumenthal said. "This legislation would have enabled people to be aware of the threats to safety posed by the faulty ignition switches, and deaths could have been prevented."