Severe Duty fan clutch by Hayden. Fits 1st generation Chevrolet Silverado/GMC Sierra HD with the LLY 6.6L diesel engine.
When fully engaged, Hayden Severe duty fan clutches can keep the fan spinning at up tp 90% of shaft speed. This improves airflow through the radiator and around the engine, improving cooling significantly. This is a must have upgrade for those who tow frequently especially up high elevations or in high temperatures.
