2000 Cadillac Escalade Owner's Manual - Page 277

Engine Air Cleaner/Filter The engine air cleaner assembly has an indicator that lets you know when the engine air cleaner/filter is dirty and needs to be serviced. The indicator is located on the air intake tube between the engine air cleaner and the engine. See "Owner Checks and Services" in the Maintenance Schedule booklet to determine when to check the indicator. If the area inside the clear section of the indicator is green, no engine air cleaner/filter service is required. When the area inside the indicator is orange and CHANGE AIR FILTER appears, the filter should be replaced. Your engine air cleaner/filter is located between the battery and coolant recovery tank. 6-15