Land Rover FC101 Transmission.

The coupling (above) for the powered trailer contains a spline with which the fitting on the trailer engages. Power is supplied by a propeller shaft from a special transfer-case power take off (PTO) unit.

The normal propeller shaft passes from the transfer case, with its hand-brake drum, to the heavy duty Salisbury rear axle (5.4:1). The trailer propeller shaft passes over the rear axle (left) and is fitted with a universal joint where it does so.

The 4-speed LT95 transmission has two PTO units fitted. The trailer-drive PTO replaces the gearbox mainshaft output bearing and its carrier. An additional PTO for a hydraulic winch can be seen below the trailer drive. The standard military winch for a Land Rover 101 is the Nokken mechanical winch, but this prototype 101 has been fitted with an alternative at some time in its long career.

Although it shares the same axis as the main gearbox output shaft, the trailer PTO is instead driven by the (constant mesh) low-speed cog on the transfer case intermediate shaft. In this way it revolves at same speed as the 4x4's propeller shafts in both low-ratio and high-ratio.

Note the safety hoop fitted around each rear propeller shaft. Its purpose is to catch the propeller shaft if its front universal joint fails. Without a safety hoop, the shaft could then dig into the ground and "pole vault" the rear of the vehicle into the air or sideways - possibly fatal in either case. At any rate the shaft would be badly damaged without them. Does your truck have similar fittings?