I was messing around with my setting a few days ago and I completely lost signal. One reason I think that we lose data is that under in the Network Mode in the Mobile Networks section of the settings there is no way to select LTE/CDMA/EvDo which is what gives you 4G. Every time you go into the section you go back down to 1x.
Here's how to get 4G back. The method was posted a few pages back.
- Settings > Wireless & Networks > More... > Mobile Networks
- Change the Network Mode to CMDA/EvDo auto
- Settings > Interface > System > Notification drawer
- In the Widget buttons you need to add Toggle LTE
- Turn on the LTE and you will get 3G
- Install 4G LTE Switch from the Play Store
- Make sure the app is freshly opened, force close it to make sure
- Open 4G Switcher
- Under the "Set preferred network type:" select LTE/GSM/CDMA auto (PRL)
With all of this you should have 4G back. There is no need to keep the app or keep the LTE toggle in your notification drawer so you can dispose of them as you wish.