I'd clean it up, anyway, just on general principles. I think you'll do better with proper way oil, not too heavy. I had an idea once that #40 synthetic oil would be just the thing for preventing wear on my lathe ways. I discovered that it created such a thick oil film the carriage floated around by as much as a couple thousandths of an inch, so accuracy suffered. The grease may be having a similar effect.
----------
Try to make a living, not a killing. -- Utah Phillips
Don't believe everything you know. -- Bumper sticker
Everybody is ignorant, only on different subjects. -- Will Rogers
Law of Logical Argument - Anything is possible if you don't know what you are talking about.