Subject: Re: Driveshaft grease
If your input and output shafts are more or less parallel to each other, but move laterally with respect to each other, the best setup is to have the yokes on either end of the shaft parallel to each other, not at right angles. U-joints are not perfect when running at an angle, and although the diff may be running at a steady speed, the driveshaft will vary in speed. By aligning the yokes on the shaft in parallel this effect cancels out and the wheel should run at a steady speed.
Alec