are you sure you have a 4440 2 speed? They were a direct-overdrive. The 4440, 4450, 4455, were the only ones to use the direct-overdrive. The replacement gears for the planetary on the s speeds are a helical cut gear, whereas the original 4440's were straight cut gears.
The rest of the 2 speeds were underdrive-direct like the 4030, 4230, 4430, 4630, 4040, 4240, 4640 used.
A 4430 2 speed installed in a 4440 would slow it down, and the gears would shift backwards.