Horton’s Modulator Fully Variable Retrofit Packages are designed to deliver optimized engine cooling and replace on/off fan drives for select heavy-duty line-haul and severe-duty vocational trucks where pneumatically actuated fan clutches over-cycle or do not provide optimum performance. The retrofit packages maximize engine power to the vehicle drive wheels and are engineered to offer faster cab warm-up, more efficient air conditioning and quieter operation.
Two Modulator retrofit packages are available: The package for specific Cummins engine applications contains the Modulator RCV250 Fan Drive assembly, the retrofit installation kit with Horton’s Di controller and the WindMaster HS11 Fan; while retrofit packages for applications that do not require the controller use the vehicle’s ECM to control the Modulator.


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