Q: rpm drops to idle at highway speeds, pull over and restart.

Hello. There is simply no way of knowing without being able to perform some tests, and ask some further questions. When this happens, do any warning lights come on? Even if they don’t, have the vehicle scanned for diagnostic troubleshooting codes. Some codes will set and not ever trigger the warning lights. You were right to check the battery connection right away. However, other electrical connection issues relating to fuel and spark will behave the same way. You will want to have both of these systems examined need be. It sounds like an electrical issue, or possibly a fuel issue. When the vehicle dies, does it restart and then have no issues? How much time passed between the two situations?