Shark fin antenna - am/fm radio reception

[bofus]

I was having terrible radio reception for am/fm. Satellite radio worked great and so did Sync 3 navigation. I pulled the shark fin antenna out and it had water inside and lots of corrosion. I bought a new antenna and was going to swap over the painted cover. When removing the factory painted cover, I find that two of the plastic posts inside the painted cover were broken, including the one at the very front. I managed to sorta build-up a new post with superglue and baking soda and then use a longer screw. Seems to be holding. Radio reception, including HD radio, is working great again. This is in a 2018 Ford Edge.

 

I had a 2015 Ford Edge where I upgraded the head unit to Sync 3. A few months later, I noticed terrible reception. After a lot of troubleshooting, it was the shark fin antenna with that car as well.

 

Are these things just not sealed very well? I see occasional posts here about AM reception, could they all be related?

 

Anyhow, just an information post in case others run into this. You can access the stupid thing from the cargo area and just peel some weatherstrip back to drop the rear part of the headliner. Wear a long-sleeve shirt or your arms are going to get sliced up by the unfinished edge of the headliner. It's maddening to get the 10mm bolt back in place, but it can be done.