This system was intended for improving large size engine's performance, fan noise, and vibration over precious engine's direct connection method. The basic principle for this Fluid Motivating Fan Clutch is that a fan is installed in the driven casing setting high viscous fluid around a disk typed drive axis. This is the most important part for engine cooling fan activating system for the present automobiles. This mechanism can generally be called Air Temperature Sensitive Viscous Fan Drive or Modulated Viscous Fan Drive Compatible with 96-01 Oldsmobile Bravada, 96-10 Chevrolet Express 1500, 96-10 Chevrolet Express 2500, 03-10 Chevrolet Express 3500, 09-10 Chevrolet Express 4500, 96-10 Gmc Savana 1500, 96-10 Gmc Savana 2500, 03-10 Gmc Savana 3500, 99-07 Chevrolet Silverado 1500, 99-07 Gmc Sierra 1500, 01-06 Chevrolet Silverado 2500 Hd, 96-05 Chevrolet Astro, 96-05 Chevrolet Blazer, 01-05 Chevrolet Silverado 1500 Hd, 01-05 Chevrolet Silverado 3500, 00-05 Chevrolet Suburban 2500, 96-05 Gmc Safari, 01-05 Gmc Sierra 1500 Hd, 01-05 Gmc Sierra 2500 Hd, 01-05 Gmc Sierra 3500, 02-05 Gmc Sierra Denali, 96-05 Gmc Yukon, 00-05 Gmc Yukon Xl 1500, 00-05 Gmc Yukon Xl 2500, 96-04 Chevrolet S10, 99-04 Chevrolet Silverado 2500, 02-04 Chevrolet Suburban 1500, 96-04 Chevrolet Tahoe, 99-04 Gmc Sierra 2500, 96-04 Gmc Sonoma, 96-02 Chevrolet C3500, 96-02 Gmc C3500, 96-01 Gmc Jimmy, 01 Gmc Sierra C3, 96-00 Chevrolet C2500, 96-00