Actually it is an enclosed driveshaft on these..... No torque is transmitted through the enclosed driveshaft. The leaf springs transmit the "push" or "pull" when in motion. The universal has a slip joint.
Pre'49 Fords, Mercurys and Lincolns had torque tubes. "push or pull" was transmitted by the front of the torque tube pushing or pulling on the rear of the transmission. The universal was fixed on these with no slip joint.
John
