cvbfireman, thanks for the offer, my trackbar is longer than stock by about 6" so the OEM one won't fit anymore. I have some obscure math geek stuff in mind...
Paul, I'd be interested in knowing what the aftermarket one measures. I was messing with the Euler buckling and natural frequency calculations. Both go as the square of length, so by increasing the length of the track bar from about 30" to about 36" as I have done makes a big difference in structural behavior. More likely to act like a jumprope when it gets an input from, say, a sharp-edged bump on the freeway. The frequency will still be high, but it could be enough to feel. I am getting some of that in the front end at speed. Nothing like the usual death wobble- this damps out almost immediately.
I've noticed that every full size truck I've seen that uses coil springs has locating rods (track bar, panhard rod, whatever) much larger in diameter than found on early Broncos, not to mention steering links. Arguably heavier vehicles, but not as much as you'd think, especially when you add much larger than stock tires to the mix.
I'm going to bump my track bar up to 1.25" diameter, just for grins. May not sound like much, but there's that math again: the bending stiffness of a circular rod goes as the 4th power of the diameter, so a small increase makes a huge difference in stiffness.