2005 S40 T5 Harmonic Balance Nut Fell off?

[djfinn]

I am the proud owner of a 2005 S40 T5, 117,000 miles on her. The timing belt was replaced @ 111,000, and just recently had the alternator and battery replaced about a month ago. Today while driving a ruckus began under the hood. Upon initial inspection I figured I threw a belt due to incorrect installation, called roadside and was towed to the shop. I was right about the thrown belt, but it was because the harmonic balance center nut had loosened and fell off. I was just wondering if anyone else had this happen, or can I chalk it up to reckless timing installation? I was very lucky to not of thrown the whole timing belt btw! At least that is some excellent news today.

[jimmy57]

The nut stays put for 111K then comes off 6K after belt change. It would be HIGHLY unlikely to not be the result of something done/not done at timing belt change where that was removed.