GM Service Manual Online
For 1990-2009 cars only

Your vehicle may have this feature. There is no lever or switch to engage or disengage the front axle. It is fully automatic and adjusts as needed for road conditions. Your vehicle has an active transfer case allowing two-wheel-drive operation on dry roads. The transfer case will shift automatically into all-wheel drive on slippery surfaces. You may feel an extra shift when the all-wheel drive engages.