my truck has a 4 link in the rear and is running shocks in the back and the rear of my truck sways on the highway when i let off the gas to slow down or go over some bumps and i was wondering what i could do to stop it
Your upper bars are probably too long, so one solution is to shorten the upper bars, another is a panhard bar, and another is a watts link, or you can just flip it around and make it a forward triangulated 4 link.
Well... here is the dilema with a panhard bar or watts link on a reverse 4 link..... there isn't room for one. Normally, a watts link or panhard bar goes behind the axle, and a panhard bar attaches at the axle on one side of the truck, and on the frame at the other side of the truck, and you want the bar to be parallel to the ground half way through the lift of the suspension, which means the panhard bar would be angling up if you were layed out, or angled down if you were at full lift..... well dependent on the design of the reverse 4 link, that is not possible in 99% of the cases, and their isn't room in front of the axle, cuz of the front of the differential, and the driveshaft.
A watts link is like two panhard bars from both sides of the frame that attach to the center of the diff via a bracket, that pivots in the middle, and the linkage rods connect to the top and bottom of the bracket, and rotate around the center pivot, to allow the axle to stay centered throughout the entire range of motion, unlike a panhard bar, which pulls and pushes the axle different ways through out the range of motion.