2010 GMC Terrain Owner's Manual - Page 300

9-26 Vehicle Care If the level is below the bottom of the filler plug hole, located on the transfer case, you will need to add some lubricant. Add enough lubricant to raise the level to the bottom of the filler plug hole. A fluid loss could indicate a problem; check and have it repaired, if needed. What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See Recommended Fluids and Lubricants on page 10‑7. All-Wheel Drive Transfer Case When to Check and Change Lubricant Refer to the Maintenance Schedule to determine how often to check the lubricant and when to change it. See Scheduled Maintenance on page 10‑2. How to Check Lubricant Starter Switch Check { WARNING When you are doing this inspection, the vehicle could move suddenly. If the vehicle moves, you or others could be injured. 1. Before starting this check, be sure there is enough room around the vehicle. 2. Firmly apply both the parking brake and the regular brake. See Parking Brake on page 8‑40. Do not use the accelerator pedal, and be ready to turn off the engine immediately if it starts. To get an accurate reading, the vehicle should be on a level surface.