I had to replace my windshield wiper assembly (not the motor), due to rust. When it starts going bad, it sounds like the wiper blades are sticking to the windshield and it is nails-on-chalkboard bad as it gets worse. No amount of cleaning makes it go away because it is coming from under the hood/windshield area. The noise is present when blades are up & not touching the glass.
I had Merlin send me the four parts (only 1 of the 4 pieces was in the U.S.) and a motor (also not in the States). Got the VX back today, and luckily everything is working great. I didn't even need the new motor... Espo says it's very strong (couldn't move the mechanism by hand, but the motor was still pushing it) and seems to be running well. So I have a new spare...
I would recommend checking yours f you think it might need TLC.