Should you be able to turn your front drive shaft by hand?

Well, when I put the truck into drive it bumps sometimes then it doesn't make a sound at all going down the road. It sounds like it's jerking in the rear end, then sometimes up toward the middle of the truck. The transmission seems to be doing good, so I thought maybe the drive shafts was lose, so I checked them. The u joints in the back were tight I checked the front drive shaft the one with a boot on it and it was not off the ground just in park and I could turn it both left and right by hand. I didn't know if the front drive shaft was supposed freely move like that or not.

Thats what it was in as normal driving cercamstance

Okay, I figured out what all my problems were. I got a crack in the manifold causing miss fires on 6 of the 8 cylinders because it's leaking on to the plugs and a u joint is failing in the rear end causing the bumping and jerking associated with the misfire. I took it to a mechanic, it's an expensive job totaling a little over $1,600.00 maybe a wheel u joint other than a drive shaft u joint. But you have been helpful identifying things for me and the help of the front drive shaft turning was appreciated. I realize that in park it's supposed to be able to be turned freely by hand with a little resistance, but still fairly easy to turn.