2008 GMC Sierra 1500 Pickup Owner's Manual - Page 330

How to Inspect the Engine Air Cleaner/Filter Vehicles With an Air Filter Restriction Indicator Locate the air filter restriction indicator on the engine air cleaner/filter cover. When the indicator turns black or is in the red/orange "change" zone, replace the filter and reset the indicator. See the steps following to replace the engine air cleaner/filter and to reset the air filter restriction indicator. Replacing the Engine Air Cleaner/Filter and Resetting the Air Filter Restriction Indicator 1. Locate the air cleaner/ filter assembly. See Engine Compartment Overview on page 5-12. Vehicles Without an Air Filter Restriction Indicator To inspect the air cleaner/filter, remove the engine air cleaner/filter from the vehicle by following Steps 1 through 6. When you have the engine air cleaner/filter removed, lightly shake it to release loose dust and dirt. If the engine air cleaner/filter remains caked with dirt, a new filter is required. 2. Loosen the four screws on the cover of the housing and lift up the cover. 5-18