Horton’s VMaster and Stratis Di Viscous fan drive and controller systems provide customers the flexibility of variable speed along with optimal engine cooling, reduced fuel consumption, decreased noise, and more available power for auxiliary components. The system is compatible with many Horton and competitive 20- to 44-in (508 to 1118-mm) diameter plastic, metal, and composite fans. The fan drives include a double-row bearing for increased durability, and they feature an improved fluid flow return path for better heat removal and extended product life. The system cools hotter-running, reduced-emissions engines. It features a reservoir, actuator, and valve system that delivers faster response time on the front of the fan drive to increase airflow and improve cooling. Applications include off-highway equipment, vehicles, and buses, including skid steers, truck cranes, cement mixers, refuse trucks, and agricultural equipment.