2003 GMC Yukon Owner's Manual - Page 435

Front Position Front Tire Flat: If the flat tire is on a front tire of the vehicle, you'll need to use the jack handle (C) and only one jack handle extension (D). Attach the wheel wrench to the jack handle extension. Attach the jack handle to the jack. Position the jack on the frame behind the flat tire where the frame sections overlap. Turn the wheel wrench clockwise to raise the vehicle. Raise the vehicle far enough off the ground so there is enough room for the spare tire to clear the ground. Rear Position 2500 Series Rear Position 1500 Series Rear Tire Flat: If the flat tire is on a rear tire of the vehicle, you'll need to use the jack handle (C) and both jack handle extensions (D). Attach the wheel wrench to the jack handle extensions. Attach the jack handle to the jack. Use the jacking pad provided on the rear axle. Turn the wheel wrench clockwise to raise the vehicle. Raise the vehicle far enough off the ground so there is enough room for the spare tire to clear the ground. 5-77