If they are tapered bearings you don't tighten them right up as you are wedging them together,tighten them Lightly so they are all the way home then back the nut off about 1/4 turn and check with the wheel on that it doesn't rock by holding it top and bottom and trying to move it,after a few miles jack it up and test again,if there is movement tighten them slightly and make sure the wheel revolves freely,its all a matter of touch not brute force.
Rich
January 2008