2009 Hummer H3 Owner's Manual - Page 303

Service and Appearance Care CAUTION (Continued) 3. If you have a four-wheel-drive vehicle, be sure the transfer case is in a drive gear - not in N (Neutral). 4. Turn off the engine and do not restart while the vehicle is raised. 5. Do not allow passengers to remain in the vehicle. To be even more certain the vehicle will not move, put blocks at the front and rear of the tire farthest away from the one being changed. That would be the tire on the other side, at the opposite end of the vehicle. To use the wheel blocks, lift the wheel block and lock it into place. When the vehicle has a flat tire, the wheel blocks need to be set up before changing it. The wheel blocks are located in the tool bag in the swing-gate for H3 models or below the rear seat for H3T models. See Removing the Spare Tire and Tools (H3) on page 5-68 or Removing the Spare Tire and Tools (H3T) on page 5-69 for more information. 5-67 Use the following example as a guide to assist in the placement of the wheel blocks (A) when the vehicle has a flat tire (B). A. Wheel Block B. Flat Tire The following information explains how to use the jack and change a tire.