I constantly learn new things every day, and without being officially trained to be a certified Epson repair tech, I have to rely on the printer manuals, my experience and technical abilities to learn about all the different models we use and support.
My experience has taught me that machines need to be kept clean and used regularly (or stored properly when not used) for the best results and longest life. For many years, I have been head of technical support and research & development for Inkjetmall, as well as production manager at our fine art printing studio, Cone Editions Press. This range of duties has given me a broad understanding of our products, and the printers we make them for- in both a highly technical way of using/testing/pushing products in all different ways, and using them every day in our high quality fine art production studio. I have maintained and repaired our various model printers over the past +/- 7 years, and have learned a lot (plus saved us several $thousands). From this experience, I have learned keeping a printer clean, regularly agitating pigment ink carts, maintaining proper humidity levels and using the printer will give you the best results and least headaches. The capping station, wiper blade and flushing box should be cleaned regularly, and bottom of the print head as needed (which should be fairly infrequent, provided you keep the other parts clean). I also work to keep the printers clean of paper fibers/dust, in the top paper feed path, all inside the cleaning area and paper feed path, and bottom paper feed path. Often, when a printer isn't used daily, I drape a large sheet of slip sheet paper over to help prevent dust and stuff from getting inside. I have to admit, there have only been a few times I have lightly lubricated our printers' CR shafts, and I used a Q-tip with small amount of white lithium grease (which I now read isn't the best thing to use). When I did grease the CR shafts, both times were on several year old printers that had been kept fairly clean, and dampers replaced every few years, but used a LOT. During routine damper replacement and thorough cleaning, I noticed the grease looked pretty dirty, so I carefully wiped the shaft clean, and applied a small amount of lithium grease in it's place. This seemed to work fine, and I've never had an issue with it, though your question has prompted me to want to learn more about the lubrication needs of various printers, what lubrication to use on what parts/printers, and where to get them... There's always a lot going on, but when I learn more about this, I will be sure to add info to our maintenance tips.
All the best~ Dana