The string of recalls, topped by an ignition switch problem in compact cars now linked to 13 crash deaths, has embarrassed the company and sidetracked its new CEO, who started work just over two months ago.
GM has admitted knowing about the switch problem a decade ago, yet it didn't recall any cars until February. The recall delay has brought two congressional investigations and probes by the Justice Department and the National Highway Traffic Safety Administration.
Last night, GM announced it would recall 490,000 late-model pickup trucks and SUVs because transmission oil cooling lines weren't secured properly in their fittings. Transmission oil can leak from a fitting and hit hot surfaces, causing fires, the company said in a statement.
GM said it knows of three fires and no injuries.
The recall affects Chevrolet Silverado and GMC Sierra 1500 pickup trucks from the 2014 model year, as well as 2015 Chevrolet Suburban and Tahoe SUVs and the GMC Yukon and Yukon XL SUVs. All have six-speed automatic transmissions.
The Silverado is GM's top-selling vehicle and an important profit center for the company. The GMC Sierra also is among GM's top sellers.
Dealers will inspect the transmission oil cooling line fittings and make sure they're securely seated, at no cost to owners.
GM also announced yesterday the recall of 172,000 Chevrolet Cruze compact cars because the right front axle shaft can fracture and separate while being driven.
The recall affects cars from the 2013 and 2014 model years equipped with 1.4-litre turbocharged four-cylinder gasoline engines.
If a shaft fractures, the wheels would lose power without warning and the cars would coast to a stop.
GM says it has warranty reports of several dozen shaft fractures. It is not aware of any crashes or injuries. Dealers will replace the shafts free of charge.
The recall allows dealers to resume selling affected Cruzes. GM issued a stop sale order on the cars Thursday night.
The recall also covers about 2,500 replacement shafts used to fix manual transmission Cruzes that were recalled last September.