Just wanted to show what happened to my crankshaft pulley. It started noticing it making a squeal notice every so often. Especially with the a/c on. The looked at it while the ac was on and saw that it was wobbling realllly bad. Turns out this thing was totally separated from one another. Anyway. Got it replaced and works fine now. Almost went with the ralco rz lightweight pulley but decided to go oem

https://www.dropbox.com/s/fbxuljlt0409owb/2014-08-21%2018.34.38.jpg

 

What happened to you is not an isolated case. Nissan should have done better with the design.