GMC 2002 Yukon XL Owner's Manual page 310

Rear Position Rear Position
1500 Series 2500 Series
Front Position
3. Make sure the jack head is positioned so that the rear
axle is resting securely between the grooves that are
on the jack head. 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 fit back underneath the rear of the vehicle.
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