It darts but not by much. Just enough to annoy me. I can still drive on the road with it.

 

It darts but only by a little each time I pass the center spot in the steering. I was thinking pitman arm but just wanted to be sure.

 

I hope you get some good answers as mine does the same thing. It's all been rebuild accept replacing king pins and has a new rebuilt steering gear. I replaced the rag joint with a Borgeson u-joint coupling thinking that might be the problem. Hope some body can help us. JIM

 

Did you ever get this figured out? Just picked up a 77 F100 2wd and it is doing the same thing. I had a mechanic/alignment shop check it out and the alignment and front end components are all good. The steering box and rag joint had been replaced before I got it. Seems pretty tight at the top of the steering movement though. He recommended putting new shocks on it before we go to the steering box. He also said the PS pump is going bad, lots of whining.

 

I actually just had the whole steering replaced from a 77 to 78-79 because they don't make pitman arms for lift kits.