[Supershafts]

I think some of you are mistaking some things as per ability and bar diameter and what it actually does.

Lets say he was pulling 30,000 lbs. . . now he has a 4 link with a trac bar vs leaf springs.. .
He now has 4 solid axle locating devices rather than 2 flat pieces of spring steel wrapped around a bushing with a bolt thru it at each end (in reality you only have 2 mounting points and 1 flat piece of steel locating and keeping the axle under the truck), it's only the main leaf that keeps the axle centered, with the 4 link you really have 4 points locating it.

A 4 link with double triangulated arms like in that picture with that set up will be kinda squirrelly in a street truck and towing.

The best as far as easier is the straight 4 link with a trac bar, and the only way the rear will move side to side is if you mount the trac bar at ride height wrong, if it is mounted level at ride height then at full comp it might have a .25 to .5" difference to the left or right from center and at full drop it might have a .5" diff the opposite way (unless you're looking for teens of axle movement then you might get an 1." to 1.25")

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