The end of the driveshaft (hub end) is lubed with final drive lube, so that is no problem regarding towing.
The bigger problem is that turning the rear wheel will cause the bevel gears, the output shaft in the transmission and the clutch basket to also turn and those will not be lubed with engine oil if the engine is not running. I doubt that a few minutes of that would be harmful but I would be wary of hours of towing that way. The only way I can think of around that problem would be to pull the driveshaft, which is both a fair amount of work and would leave the front of the drive hub open to rain and road dust.
Brian
Does the engine have to be running to get lubrication to the shaft drive? I was reading an ad for a front wheel only trailer hitch and it mentioned that some shaft drives had to have motor running for some pump in the shaft.
