M/T stands for Mickey Thompson in this case and those are all terrain tread.Those are M/T's? No disrespect intended, but that's the mildest M/T tread I've seen. It looks to me to be an A/T tread which is probably why they're not any louder than your previous A/T's. Also, both M/T's & aggresive A/T's run the quietest when they're new, so enjoy the silent period for now.