Alright, hope this helps someone
. This past week I tried everything again because I was on my third BB and didn't want it to go back. I have tried reloading the OS, taking out the memory card (reformatting) and I also contacted TMO to get a new sim card thinking that was the only other thing I didn't change.
However, I have to say when I got my new BB I loaded all the apps (which are only two). I have ETrade app and Pacman. This past weekend I took off ETrade and left Pacman on. Shortly afterward the device rebooted.
I couldn't take it any longer so I deleted Pacman. After two days, there were no reboots. I placed ETrade app back on and still after a few days now, no visible or known reboots. So my thoughts are that it was maybe Pacman. If I experience anything else, I will let you folks know.
Thanks again for everyone's help.