So as I'm sure everybody knows any of the current methods for getting Wi-Fi Tether for root users working on the latest version of android on the T-Mobile Galaxy S4 has been unsuccessful...
I've done an awful lot of searching and I'm proud to say that I have found a way to get free Wi-Fi tether working on the latest version of android on our T-Mobile Galaxy S4
This method involves flashing a custom kernel. In reality, this actually is a stock kernel with only one modification, Set UID Off.
Originally the only way that you could flash these kernels was to have a custom recovery because they only came in zip format. I did not want to have to flash a custom recovery every time I wanted to go back and forth between kernels, so I fired linux and made myself some odin flashable files
All you have to do is download all the files that I have listed at the end of this post.Flash The custom kernel to your phone and then Wi-Fi tether will work fine with no issues whatsoever
Once you have your Wi-Fi tether application installed simply go to your device profile change it to Samsung galaxy S3 change your setup method to the fourth selection from the bottom make sure you have routing fix and mss clamping enabled and the next time you start Wi-Fi tether it will work absolutely fine
I did not make this kernel myself I downloaded this kernel over on xda developers it was provided by the user aznmode. All credit goes to him for actually making the modification. The only thing that I am responsible for is converting the files from zip format into flashable odin files
Modified Tethering Kernel
I have also posted a video that I made showing step-by-step instructions of how to do this
LATEST VERSION WORKING ! UVUAMDL!How to Get Free WiFi Tether/Hotspot on T-Mobile Galaxy S4 SGH-M919! - YouTube