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For 1990-2009 cars only

Information on the Proper Air Filter for the Duramax Diesel

Subject:Information on the Proper Air Filter for the Duramax® Diesel

Models:2001-2005 Chevrolet Silverado
2001-2005 GMC Sierra
with 6.6L Duramax® Diesel Engine (VINs 1, 2 - RPOs LB7, LLY)



The Duramax® air filter, P/N 25332443, is specific to the diesel engine due to the operating characteristics of a turbo charged diesel engine. The turbo allows for a much greater air volume rate than a normal aspirated engine. The Duramax® diesel air filter is reinforced to eliminate damage from the increased airflow of the turbo. The reinforcement is visually identified by the five ribs of epoxy that lies across the pleats of the clean side of the filter.

If the correct air filter is not used, the filter may collapse or be torn in a Duramax® application. This damage will allow dust and dirt to be ingested into the turbo and engine causing serious damage. This damage is usually identified at the turbo vanes as well as extreme wear in the cylinder walls of the engine.

There is evidence of gasoline engine air filters being used in the Duaramax® application. The 8.1 gas air filter, P/N 25313349, will fit into the air box of the Duramax® diesel; however, it does not have the required reinforcement of the diesel air filter. The 8.1 liter gas engine air filter should never be used in a Duramax® diesel engine.