DETROIT, June 30 (Reuters) - U.S. safety regulators have opened an investigation into an estimated 260,000 model year 2005 Dodge Ram 1500 pickup trucks of Fiat Chrysler Automobiles because a loose fastener may cause the rear axle to lock up or detach.
The National Highway Traffic Safety Administration reported the investigation over the weekend on its website. NHTSA said it has received 15 consumer complaints on the issue. Loose pinion nuts are suspected to have caused the problem, the government agency said.
NHTSA also said the consumers who had complained about the problem said there was little or no noise or other warning before the lock-up or separation of the rear axle. NHTSA said consumers reported incidents that occurred at speeds of 50 miles per hour (80 km per hour) or greater, and that two alleged the trucks went into an uncontrolled spin.
"It was five seconds of terror that I thought would surely end in disaster," said one driver who said he had been traveling at 60 mph (97 kph) on an interstate when the rear wheels locked up. He was able to limp his truck to the side of the exit lane as other vehicles sped by.
A preliminary evaluation may eventually lead to a recall, but does not always do so. The consumer complaints have not yet been fully vetted by the automaker or NHTSA.
In February 2013, Chrysler recalled 370,297 vehicles, including Ram 1500 pickup trucks from model years 2009 to 2011, for similar issues.
A Fiat Chrysler spokesman on Monday said the company is cooperating fully with NHTSA. (Reporting by Bernie Woodall; Editing by Paul Simao)