Aloha Tom,
If the tube and drive cable are not installed in the car now would be a good time to remove any hardened grease with mineral spirits. If the tube is installed in the car, remove the cable and clean with mineral spirits to remove the old grease. As long as the cable can reinstalled with out binding or stopping before the end of travel it should be fine. Liberally coat the cable with grease and slide it back in the tube. I would use either general prpose white grease because it doesn't seem to harden or a water proof grease like that used on boat trailers. Make sure that the wiper motor gear box is also lubricated well. Good luck.