The paddle or piston is 99% of the wiper motor rebuild. There really isn't much else that can go wrong with them. If you’re careful you can get away without replacing the gaskets. I have been trying to find out what the material is that is used in the paddle. It isn't leather as I first suspected, it looks like some sort of woven fabric, and it appears to be impregnated with something like graphite??? If anyone has any information at all about this I'd sure like to hear it. Out of our 20,000 plus membership, there must be someone here that that could shed some light on this. There was a time when the rebuilding kits were available for the service station or garage to rebuild the wiper motors.
Although it has been suggested that the motor can be oiled thru the vent holes I'm just wondering what Ficken has to say about that? ATF squirted in the vacuum line is a popular fix I hear often, but that to me sounds only temporary. I do know that Ficken uses grease on the piston, because they told me that, and I believe that would be all the lubrication that is necessary until the next rebuild. If the grease has dried up then it’s probably time to disassemble and rebuild.
DG