See also:

When to Inspect the Engine Air Cleaner/Filter
Inspect the air cleaner/filter at the scheduled maintenance intervals and replace it at the first oil change after each 80 000 km (50,000 mi) interval. See Maintenance Schedule  for more info ...

Reporting Safety Defects to General Motors
In addition to notifying NHTSA (or Transport Canada) in a situation like this, please notify General Motors. Call 1-800-521-7300, or write: Buick Customer Assistance Center P.O. Box 33136 ...

StabiliTrak® System
The vehicle may have a vehicle stability enhancement system called StabiliTrak. It is an advanced computer-controlled system that assists with directional control of the vehicle in difficult driving c ...