EDITOR'S NOTE: This story has been corrected to note that the service bulletin says the problem could require the replacement of the wheel bearing assembly.
LOS ANGELES -- Toyota is taking action to fix the latest in a series of quality problems related to the drivetrain of its full-sized Tundra pickup.
The company has released a technical service bulletin that covers the rear axles and differentials of 2007-10 model Tundras. Toyota describes the problem as a "growling noise" coming from the rear axle-shaft bearing.
The service bulletin says the problem could require the replacement of the wheel bearing assembly.
The noise often is a sign of wear on the rear-wheel bearing, which if it fails can result in a loss of steering control or the separation of the wheel from the vehicle.
About 500,000 Tundras have been built since 2007, when the vehicle was redesigned. All still fall under Toyota's powertrain warranty. There are no plans to extend the warranty on the affected vehicles.
Toyota spokesman Brian Lyons said the automaker has received "very few complaints" about the problem. He said the problem usually involves "tolerance stack-ups within the third member that usually are heard early on in the life cycle."
In 2008, a similar growling noise from the front differential of 4x4 Tundras was the focus of another technical service bulletin. In 2009, Toyota issued a bulletin conceding that Tundra automatic transmissions could slip out of gear because of clutch damage.
Also, a 2008 service bulletin noted that the truck's balky driveshaft could cause a "bump from behind" feeling during acceleration from a stop, but Tundra-follower Web sites reported that the problem could result in driveshaft separation at high speed.
According to a 2007 service bulletin, the torque converter was reported to have a "shudder."
Meanwhile, investigators continue to look for causes of uninintended acceleration on some Toyota vehicles. The company has issued recalls of millions of vehicles to fix sticking accelerator pedals and interference by floor mats that it concedes can cause the problem. Toyota says other possible explanations include driver error.
But the company says that after reviewing 3,000 complaints of unintended acceleration since March, it has found no evidence that electronic software glitches are the fault.
Separately, Toyota confirmed last week that it had been subpoenaed by a federal grand jury in the Southern District of New York concerning the recall of "defective, broken and/or fractured steering relay rods" in its vehicles.
Toyota would not say what vehicles are involved in the investigation, and the court did not provide additional information. In a statement, Toyota said it "intends to cooperate with the investigation."
In 2004, Toyota recalled trucks that had been built over a six-year period in Japan, citing steering rod flaws. U.S. executives told regulators at the National Highway Traffic Safety Administration that the recall was limited to Japan market vehicles.
But 12 months later, Toyota's U.S. operations recalled nearly 1 million compact pickups, T100 trucks and 4Runner SUVs for the same problem.