Sharing my latest transmission story for what it's worth. I currently have 50k on the car, had transmission service/AB conversion kit done at 35k and a transfer case fluid flush at 45K to try and resolve a slight buzzing noise that occurs at the end of each shift. You can only really hear the buzz during gears 2 &3 at around 2800rpm or when down shifting to accelerate away on the freeway. Transmission flush seemed to help temporarily, but noise came back, and transfer case flush did nothing. Incidentally, The transfer case(pun intended) was interesting. As instructed, my mechanic tried to do a transmission update after the transfer case flush, and it wouldn't take, he thought for moment that an internal electronic shift component which takes a pounding from heat decided to take a you know what and die. At the time my mechanic was stressing because no matter what he did the update wouldn't take and theres' no way he was going to call me back saying the car you brought me in good working order is now dead, and we're gonna need 3K to bring it back to life. So to his testament, he spent the next 48hrs sourcing and trying various firmware fixes. After speaking with all his landcover tech buddies/vendors it looked like the worse had happened as it's pretty common for this internal electronic part of the transfer case to fail. He then called one of his smaller vendors who told him to try his firmware update. And sure enough, update took and car was good to go. Incidentally, I still have that buzzing noise, but I'm not sure what else can be done at this point unless whatever it is fails, throws a code or something. For the record, buzzing was prevalent with original tranny oil still in the car. Doesn't appear to be getting any worse, than it was 25k ago, but time will tell.