GM Service Manual Online
For 1990-2009 cars only

Vehicles with a limited-slip differential can give more traction on snow, mud, ice, sand or gravel. It works like a standard axle most of the time, but when traction is low, this feature allows the drive wheel with the most traction to move the vehicle. The limited slip design has minimal impact to the steering feel, but boosts the traction performance under all conditions.