Well as far as i'm concerned it is. if you buy a reman using the part # 277580 you will get the plow option with the benefits i mentioned.
if you buy the reman using part# 277588, you will get the non-plow with the bad turning radius and less power. plain and simple. after buying and trying both part numbers i can attest to this. one thing to note; there is no difference in the numbers stamped on the case, so if you grab your box from the wrecker you won't know which is which until you try the gear itself. but if you buy a reman using the correct part number, i'm betting you'll see the same results. i also found that the plow option is only available on the 98 Durango and not the 99. -B
Since both numbers on the case are the same they are sold as the same item regardless of whether it uses a snow plow or not. Autozone doesn't even differentiate the difference between plow or not. I know about 6 people that have gone with the Durango box and 2 of them got 'lucky' to get the 3.5 turns.