Today a new root method was released for many LG G3 variants. This should root the latest updates which have been unrootable. Unfortunately this will not work for the LG G4, but may be updated later on to support it. You can flash this file manually via adb, or you can use the one click script. To root with the script simply download, extract, and then double click root.bat. Works on Windows only. Grab this script from the link below.
via XDA