The National Highway Traffic Safety Administration (NHTSA) has begun an investigation of defects in Volvo trucks that came in response to a petition submittedlast year by the Owner-Operator Independent Drivers Association (OOIDA).

The investigations focus on steering problems, front u-bolt problems and sleeper berth fires, and join an ongoing NHTSA inquiry of rear u-bolt problems in trucks built by Volvo Trucks North America.

The problems Volvo owners reported with u-bolts to OOIDA include unusual loosening, stretching, twisting and complete sheering off of the bolts. The causes of steering problems reported include front-end shaking and shuddering and steering column lock-up. Volvo owners attributed reports of sleeper berth fires most often to problems with the electrical system.

Volvo has said it has contacted several of the owners, and that maintenance appeared to be a factor for most of the performance issues.

In March 2001, Volvo recalled 1,577 heavy-duty trucks built between November 1997 and August 1999 because they were shipped with inaccurate front axle weight ratings. The recall stemmed from incorrect tire rating information used to calculate the weight ratings.