the amc eagle's central differential behind its torqueflite automatic transmission was single-speed (without a low-range option) and used a viscous fluid coupling for quiet and smooth transfer of power to the axle with the greatest traction, on wet or dry pavement. the central unit consisted of closely spaced, wavy clutch plates operating in a "honey-like silicone fluid" performing a "limited-slip function" between the front and rear drives, as well as under adverse driving conditions sending torque to the axle with the most traction.