out of control steering after hitting a bump

I read a dropped pitman arm was not necessary for a 3 inch lift, only larger lifts ( i believe even on some lift kit web sites). I then assumed the resultant angle was acceptable. (***..u..me) Easy to change a Pitman arm? How do you decide how much of a drop, and do they have to be custom made? Am I wrong to assume the dropped pitman arm will be more for bump steer?

 

It doesn't matter how much lift you have, it's the drag link angle that matters in this case. Measure to see how far down the steering box end of the drag link comes down so it's parallel with the tie rod then see what drops are available for the steering box you're using and what fits the drag link end.
Yes, the dropped pitman arm is to cure bump steer. This is one of the things causing your death wobble and needs to be addressed.

I use a steering stabilizer to act as a damper off road like Corveeper said in his post. Many 4x4 vehicles come with them from the factory. They are not to fix a steering or suspension issue, just to dampen the backlash of the tires hitting an obstacle.

 

How does one find the size of the tie rod end? I used the heavy duty setup from Herm with the revers Ford power steering system.

 

BY the way, what is the difference between a manual and power steering dropped pitman arm? There seem to be different ones...

 

Jeep used the same taper and length on the tie rod end studs from '42 until at least '86. If you have Jeep tie rod ends than that part isn't an issue. The threaded end came in several versions depending on application. If Herm supplied you with the parts he should be able to tell you what he supplied.

Manual Saginaw boxes used a smaller diameter pitman shaft and power used a larger diameter pitman shaft typically. '76 and newer CJ's used a different "clocking" of the pitman arm than '72-'75. Again, you may need to contact Herm about what fits with his set up.

One of the reasons I don't like his set up is all these common issues that continually come up that are minimized with a standard Saginaw steering conversion.

 

Just been back and forth with Herm via email. He runs a 5 inch lift with his PS conversion. No dropped pitman arm. No issues. Still, looking at a dropped pitman arm, puts the drag link down parallel with the long tie rod. I read something about interference when the suspension flexes. Trying to visualize this problem, how can it happen? Would there be an issue with the rods trying to hit the arm at flex since it is down near the rods?
Or is my 3d visualization all screwed up from my younger years?
Thanks,
Paul

 

Pretty hard to answer till you tell us more about your younger years

 

Ok. I’m taking a guess here but I imagine what they’re talking about is that your suspension doesn’t cycle straight up and down.
As an arched leaf spring compresses it extends, that’s why a shackle is used to allow room for the leaf spring to extend and retract as it compresses and droops. Since your axle is located, held in place under the chassis, by the leaf spring when the suspension compresses the axle will move up and towards the shackle. In your case with the shackle reversal that means it will move up and back.
Taking a second look at your setup that may actually be an issue because getting the drag link parallel to the tie rod means placing the tie rod end at the pitman arm between the tie rod and axle tube.
This is starting to sound like one of those issues nickmil mentioned that isn’t such a problem with a standard rotation box.

 

As far as dropped arms go (if you're still looking for one), try finding one for the vehicle which your box came from. i.e.-ford ranger, bronco, etc. Any of the companies that make lifts for these vehicles should also manufacture the pitman arms.


Edit: Just realized the taper would be wrong, guess that wouldn't work.

 

If the taper or hole were smaller it could be reamed out to the right hole size and taper. I've done it to many pitman arms.

 

Nickmil, never thought of that, maybe a ranger arm would work? I think all the boxes are pretty much the same, from full size bronco to ranger. I would think the ranger would have smaller tie-rod ends though. I'm assuming herm does something similar to the arms he sells with his kit.

 

I have made tapered bushings to slide in the taper to tighten the hole up, in fact my pitman and project71-5 (Joes) are both sleeved with these brass bushings due to the large GM tie rod ends versus the smaller jeep ones.

 

JEEZ the only thing that clean on my 58 is the KEY! Nice job on the resto! How about some more pix?

 

are your tires balanced if so have they lost a tire weight maybe when you hit the bump?

 

Hey Matt, check out my photobucket..click on the 57 CJ5 resto

http://s991.photobucket.com/home/85md/index

 

They were balanced... I had them set to about 27 pounds of pressure. I will have them checked again.

 

I second the fact that it can be king pin bearings, among other things. People rarely adjust them, and they wear loose.