big difference between weight distribution and sway control!!
weight distribution is accomplished with the two spring bars that connect the hitch to the aframe of the trailer. they transfer hitch weight to the front wheels of the tt
sway control is accomplished with a dampening device between the tt and truck, it works in the horizontal direction only.
weight distribution systems will do nothing for sway unless you get into the upper end(price wise) systems
we tow a 4000 lb tt(loaded) with a dodge Dakota, we use a good but not high end wd system and separate sway controller