Today I fixed my steering problem.
To start off, this definately applies to the astro van steering box. I used an astro van steering box on my ZJ because I stretched the front 7" and the astro box turns the pittman arm around facing forward so the box does not have to hang off the frame in front of the front axle. The Astro Van box bolted directly up to my frame and everything worked perfectly except my turning radius sucked. My axle was no where near turning all the way to the stops when the steering box bottomed out on its internal stops.
I've been researching how to remove the internal stops in a saginaw steering box. I found out that the end cap has the left turn stop, and there is supposably a snap ring somewhere inside the box that makes the right turn stop. This only applies to boxes that dont have 87 degrees of pittman arm rotation. My astro van steering box did not look like it was turning the pittman arm 87 degrees. Out of all the articles I read, noody actually showed where the snap ring actually was or how to remove it. Most articles I read said to replace the box with a different one that didnt have internal stops. That was no help to me because I needed the astro box because of it's reversed turning angle.
Heres a good article from Pirate about dissassembly and reassembly of the steering box
http://www.pirate4x4.com/forum/general-4x4-discussion/570869-saginaw-box-rebuild-how.html
Heres the two different end caps, the cap with the four tabs is the Astro van cap. The other cap is off the factory ZJ steering box. On the Astro box, the four tabs stop the piston preventing it from travelling all the way to the end of the box. As you can see the tabs are about 3/16" tall.
And heres the snap ring, once you remove the pittman shaft, and the piston, you can look down into the box and see this snap ring, a little work with a screw driver and it'll come out. Once the snap ring is removed it's time to reassemble the box and enjoy full steering.
The screw driver is pointing to the snap ring in this pic
Heres the same view with the snap ring removed
Heres the snap ring as you can see it's also about 3/16" thick
