RTAWD Retrofit Viscous Coupler

An understanding of the OEM market's failure points has led to the exploration of various technological avenues, ultimately benefiting the motorsports sector. One significant development is an internal "Viscous Coupler," inspired by Honda's 1980s innovations. This coupler provides stable hydraulic power transfer from the engine to the rear differential in the Honda Civic RT4WD Shuttle, enhancing performance against competitors like Subaru and Toyota.

The coupler's design improved immediate power transfer and responsiveness to terrain changes, reducing damage to the rear differential and transmission by dampening shock during drivetrain engagement. Although Honda's original designs were discontinued, advancements in scanning and engineering analysis have enabled the recreation and modernization of this technology.

Currently, this coupler technology is applied to the Honda CR-V as the "RTAWD Clutch Retrofit," which replaces the older external configuration. It features a precision-cut stainless steel plate design that enhances fitment and performance, utilizing the original viscous coupler's internal housing spline design. This innovative design converts the RTAWD differential into an RT4WD unit, utilizing hydraulics for torque transmission and promoting heat dissipation, ultimately reflecting a grassroots approach to development that leverages aerospace manufacturing to optimize motorsport innovation.

AKDBuilt Performance Inc
Bisimoto Engineering
SOLIDWORKS
GoEngineer
Dassault Systèmes
Honda