USB thumb drive for music ??

I have a 2015 factory navigation head unit in my truck. I'm trying to find out about putting music on a thumb drive. I need to know the max size of the thumb drive and what file types the radio needs to see. Also, if the music is in folders, can the radio play them. I have the owners manual for the radio but I don't see it.

I do use Bluetooth and occasionally plug the phone into the USB port.

 

Mine won’t recognize anything bigger than 8 gig and formatted with fat 32. When I right click on the folder that copy to the drive it will read the music in other folders that are in the main. But I have a 17 that doesn’t have the navigation.

 

There are lots of people on here saying it isn’t a max drive size, but a max file quantity. I believe I’ve seen people say it maxes out at 9999 tracks. Some people said they had to split that into 4 sub folders to get it to recognize

 

I used a 16gb sandisk cruzer fit while I had my oem radio. I don't think I had over 10k songs, so not sure about the above comments. I always separated my music into folders anyways, so I never had problems with playback.