Which do people prefer to drive 5/6 speed or a automatic. Which gives you more power and acceleration. and just in general which do you prefer

 

I have driven all three but the 5spd was in a 91 so what is said about that might not be applicable to the NV4500.
For driving around I liked the auto, it got going fast and got good milage, but the truck had 3.53 gears which was the good for the milage, but I cussed that transmission (47RE) up and down towing. I would not get as good of milage towing as the 91 5spd did. But the gearing on the truck had a lot to do with that. The 91 had 4.10 gears and still got 19-20mpg in town, never really tested it empty on the road.
What I am comparing is apples and oranges with the 6spd. I have an 04 and my dad has a 00, both 6spds, when it comes to towing having that extra gear makes it easier to get to speed and hold town speeds. Having that extra gear to go through repetitively seems harder on in town mileage though. And if you are drag racing it means one more time to dump the turbo boost.
The problem I have comparing these trucks is mine has 3.73 gears and dads has 3.55. That difference is noticable when you have a living quarters trailer. The trailer we were pulling before has not been pulled very much since we have these newer trucks, and we did not have the big trailer when we had the other two trucks.