Hey Customtruck, welcome! And yep, those are just the kinds of pics they were asking for. Thanks.
And thanks for becoming a contributor so quickly. Hope we can help you out and get you down the road safely. Driven rigs like that myself, and it's nowhere near the fun it should be.
Someone asked already, but do you have a Detroit-type locker in the rear end? This is not always a problem, but it can be a huge part of it under the right (wrong?) circumstances.
In fact the buddy's that I drove (member Ehumaui here) was 95% the Detroit in the rear. He changed it out to a Truetrac and it was a completely different beast.
That said, your steering angles are too steep for the best street handling. And a big part of what you're experiencing. The steeper the angle, the more pronounced the side-to-side movement.
That's the big issue with a 5.5" lift in fact. The drop pitman arm and trackbar bracket are optimized for 2.5 to 3.5 inch lifts, so you really should change them some more.
The two most common "fixes" for that much lift are a trackbar riser added to the lower mount, and a TRO (tie-rod over) conversion. (edit
![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Both of which you already have and the angle is still steep enough to be a problem! That's kind of surprising, but I guess that's normal. Are you sure it's only 5.5" of lift? Probably, but a measurement would be a good thing to take at this point to be sure.
What type/age/condition are the tires in? And how much air pressure?
Someone mentioned that already too, but I wanted to reiterate about playing around with things a bit.
Things to play with:
1. Tire pressures.
2. Toe-in settings.
Things to change:
1. Make the steering angles more shallow
2. Check and maybe even change the rear diff it's a locker.
For the alignment, someone mentioned 4° positive caster and that's a good start. A mildly built Bronco can get away with as little as 2.5 and still be a sweet driving truck (mine is!) but a heavily modified, big-tired rig needs more.
Settings you should shoot for are:
1. Caster of 4.5 - 8 degrees positive.
2. Camber in the .4 to .7 positive.
3. Toe-in can vary by tire/wheel/vehicle combination. Fiddle with it in your driveway and drive it to see what you eventually prefer.
The alignment tech will tell you that the camber and caster are not adjustable. They will be wrong of course, but as far as their equipment and ability is concerned, that's true. Unless you get a grumpy old fart they won't know what to do.
Just make sure you get the full printout anyway. Even if they insist you don't need the numbers, you do for later.
If they can't give you a printout, get a screen shot with your camera.
Good luck!
Oh, and those numbers I gave you are not the factory recommendations for an Early Bronco.
But then, your EB is no longer anywhere even remotely resembling stock, so old stock numbers don't always apply.
Paul