Well to be honest. To answer your question, yes you can.. But the whole regulator with slider is fairly expensive. And the labor (minus the lubrication) to get the door panel off, regulator out is the same. The lubrication part is fairly easy, just smear where parts move. I would get some high quality greese, if you dont want to buy a big container of greese, you can goto a bicycle shop and they sale very high quailty greese in smaller containers. I would go this rout, see if it fixes it, this is the least expensive suggestion. A window regulator is a few hundred bucks. That is why there is a repair kit for them when the little plastic slider breaks. Cheaper to repair than replace..
I wish I had pictures of the door apart. The part I am talking is a long (maybe 2 - 3 foot long metal spiral thing that loosely resembles a screw). Which in reality it is a screw, the window motor uses the spiral of the screw as teeth and pushes and pull it depending on direction of window. And there is little fuzzy stuff between the spirals of the screw. For some unknown reason about 2 inches of mine got something on it or got hot to cause the fuzzy stuff to be hard. And when the PLASTIC gear of the window motor hit that affected part, the plastic gear is vibrating and doing its best to move through it. So lube it or replace it..