The 4 speed is used for daily driving in 2nd-4th gears. There are syncros in all these gears, so the advantage is of being able to downshift to 2nd gear. 1st or granny gear is generally not used. So basically you would have a fully sycroed 3 speed and a granny low. I still believe you might have driveline issues with this particular swap. The 4 speed also adds about 75 lbs to the vehicle.
