GMC 2001 Sierra 1500 Pickup Owner's Manual page 361

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