Ksiesel, correct not in 2015. They started pairing them up in 2017 upwards. But I didnt know if the technology was there yet in 15 to pair the two successfully. I read there is Lag with the extra 2 speeds because of shift points differs. But also read there is a reprogram available to correct it.
i thought i would ask incase someone has done this and no issues for sure so i can jump on the truck i am looking at.