Something wrong with starter or flexplate, truck wont start anymore

[Lil Ape]

I don't know how to best describe what is happening, but yesterday when I when to go start up my truck, It made a loud grinding sound. Like metal hitting against metal. Got underneath and found that it was something with the starter and flexplate. It looked like the starter gear wasn't fully engaging the flexplate. It looked like the teeth on the starter gear was smashing into the teeth on the flexplate. Almost like the teeth on the starter weren't slipping in between the teeth on the flexplate. I only had my dad bump the ignition over for a second so I didn't really get a good look at what was happening. Didn't want to chew up my flexplate. But I took the starter off today and took it to get tested, and it passed everything. Which I figured cause the starter is only a few months old.

The truck was starting and running just fine it seemed just a few days ago. So I don't know what caused this or why it's happening. The starter already had two shims on it My dad said something is wrong with the flexplate which I hope not. Anyone had an idea?