The good news is, paper shredder oil is very inexpensive and is simple to apply. In fact, you don't need to take your shredder apart to apply oil. Simply take your bottle of shredder oil and apply several beads of oil to a piece of paper and feed it through the paper slot just like a document that needs to be shredded. As that piece of paper coated with shredder oil is being cut by the cutting heads of your machine the shredding heads will be lubricated and the effects of the buildup of paper dust will be eliminated. Your shredder will be ready to run at full capacity and motor won't have to work as hard to shred your documents by paper shredding.
It is recommended that you oil your cross cut shredding or confetti cut shredder after every 1/2 hour of shredding. Strip cut models should be oiled after every 1 hour of shredding. It is also important to use a specially formulated, synthetic, non flammable shredding oil such as the GBC Shredmaster Shredding Oil or MBM Destroyit Oil. These oils are specifically designed to help increase shredding performance and prolong the life of your shredder.
If you remember to regularly oil your shredder and are careful not to shred things that you aren't supposed to most large shredders are designed to last for years or even decades. Happy oiling and happy shredding...