Originally Posted by cyccommute

Since you seem to have water penetration, you might want to look into better ways of keeping the water out. One way would be a Stein Grease Injector like in this thread. They show up on Fleabay occasionally.

You might also want to use a thicker oil like Phil's Tenacious Oil. It's got a much higher viscosity than other bicycle lubricants. I'd try the thinner oils first and see if they work but if the problem persists, use thicker stuff.