GMC SIERRA 2002 Manual page 387

Your engine air cleaner/filter is located in the front
corner of the engine compartment on the passenger's
side of the vehicle. See "Engine Compartment
Overview" in the Index for more information
on location.
6-20
1. To remove the engine air cleaner/filter, loosen the
screws on the housing cover. Lift the cover upward.
2. Lift the filter from the air cleaner housing. Care
should be taken to dislodge as little dirt as possible.
3. Clean the filter sealing surface and the filter housing.
4. Install the new filter.
5. Reinstall the housing cover.
Refer to the Maintenance Schedule to determine when to
replace the air filter. See "Owner Checks and Services"
in the Index.