(USA TODAY) GM has recalled all of its 2014 Chevrolet Silverado 1500 and GMC Sierra 1500 pickup trucks — its best-selling line of vehicles — as well as its brand-new 2015 Chevrolet Suburban, Chevy Tahoe, GMC Yukon and Yukon XL SUVs with 6-speed transmissions.
The truck and SUV recall, which covers 490,200 units in the U.S., is aimed at fixing a "transmission oil cooler line that is not securely seated in its fitting," GM said in a statement.
The situation has created at least three "incidents" with no injuries, GM said.
"If the line is not securely seated and transmission oil leaks from the fitting, the oil could contact a hot surface and result in a vehicle fire," GM said.
In addition to the big truck recall, GM also recalled in the past few days about 172,000 Chevy Cruze sedans for a front axle defect and added 907,700 vehicles to its recall for defective ignition switches.
The latest recalls come as GM CEO Mary Barra is scheduled to testify before Congressional committees on Tuesday and Wednesday to explain GM's actions in its expanded switch recall of 2.53 million vehicles.
In those cars, faulty ignition switches can shut off the engine and disable the airbags. GM says it knows of 31 accidents and 12 deaths linked to the switches.
The cars recalled for the switch are the 2005-10 Chevrolet Cobalt, 2007-10 Pontiac G5, 2003-10 Saturn Ion, 2006-11 Chevrolet HHR, 2006-10 Pontiac Solstice and 2007-10 Saturn Sky.
GM says its engineers say the cars are safe to drive if drivers use only the ignition key with nothing attached, not even the key fob.