( I'm assuming you have a 273/233)
The driveshaft I mentioned is between the engine and HST unit. Older models have a straight shaft, with locking balls and collars at each end. Newer models have a shaft with a slip yoke and universal joints at each end ( pinch bolts at both ends). That's the easiest way to tell which design you have and I forget when TYM started installing the new shafts in production.
Greasing the ball and sleeve coupler will probably only quiet the shaft temporarily. Grease collects dirt and debris and this will only shorten the life of the older style shaft. They are not that bad to install, BUT, if you wait too long, it will wear out the splines on the HST input shaft, which requires Transmission removal to replace the shaft.
Best thing would be to get the correct shaft for your application, and install it. If you plan on doing it yourself, grab a hyd filter while your out.