you can download the root exploit from the link below, and to use it you’d need a Windows PC since it’s a couple of .bat scripts you need to run. More in the instructions below:
Download Root for T-Mobile and Verizon Xperia Z3
÷INTRUCTIONS:
Warning: Warranty may be void of your device if you follow the procedures given on this page. You only are responsible for your device. We won’t be liable if any damage occurs to your device and/or its components.
Important Note: Backup important files stored on your device before proceeding with the steps below, so that in case something goes wrong you’ll have backup of all your important files.
1-Download and extract the D6616_root.zip file from the link above.
2- Setup ADB and Fastboot on your Windows PC.
3- Enable USB debugging on your Z3 and connect it to your PC using a USB cable.
4- Double-click/Run exploit.bat file from the folder where you extracted files in Step 1.
5- Let the script run until you see the success message as shown in screenshot below:
Now wait for your Z3 to automatically reboot, after which it’ll be rooted.
Enjoy!