I am working on my '79 F350 with the d60 front end, the steering got real tight on it and will catch and grab at points, i quit driving it on the road until i figure this out, i have changed out the power steering pump and power steering box out of a working parts truck, now when i try to bleed the power steering system it is blowing fluid out when i go from side to side, i don't even have it filled anywhere near full. The steering is still tight also! I have jacked the front end up and nothin is visually loose and seems tight. The "u" joint on the steering shaft has very little play in it which is my next point to attack, but any other suggestions, esp the power steering pump bleeding. Maybe i am missing something! Thanx

 

Have you checked the axle's ujoints ?

 

the fluid blowing back is a stuck "spool" type valve in the steering box by the sound of it. The sticking sounds like a axle U-joint or ball joint trying to seize up.

 

This truck does not have ball joints in the axle. It has trunion bearings (called king pins) which really do not have any type of seal to protect them from the elements. These have to be kept full of grease and thay have to be taken apart and cleaned. While the upper is a simple frition bushing, it can break, and fall apart. The bottom is a bearing, a real tapered bearing (National part number 23100) and it has no seal. It relies on the grease to prevent any debris or junk from getting in there.
Isolate the steering and start narrowing down the problem. Typically I remove one end of the drag link so that the steering box is seperate from the system. Then I turn the steering wheel by hand with the engine running from stop to stop. If the problem persists, you can assure that you have a problem in the steering box, and you can stop looking. If the problem goes away, then you simply look down the chain and determine what is causing the binding. Veryfy that the links in the drag link function, and are not siezed up, then the tie rod ends, and often I remove the drag link. By turning the front wheels by hand individually, you can determine which side has the bad trunion bearing. This wheel will be difficult to turn by hand, and you will have isolated your problem.
Removal of the upper caps are easy, but the bottom one can be a pain>
Since I suspect that some of your problem is one of the lower bearings, I can offer a bit of advice.
Once the weight of the truck is removed from the front wheel, and the wheel is removed, take the pressure off of the upper bushing by removing the steering arm, or the spring retainer / cap.
Remove the lower 4 bolts, and lightly tap the lower cap t rotoate it. Once rotated, it will expose one corner and will permit you to tap it with a hammer. Being careful not to destroy the flat surface, you can drive the ccap down out of the bearing. Bearings that have been neglected can be troublesome, and this makes cap removal difficult.
While, I believe that your steering box is the problem, you may pay attention to the areas above, as these too lead to steering trouble.

 

I wonder if the kingpins are siezed somewhat causing the tight spots. Like 75f350 said, try it with the drag link disconnected. The problem with your fluid blowing out - did you twist or kink the pressure line shut changing the box? Are one of the hoses ruptured on the inside? If not, I think you may have problems with the donor box too.

 

Thank you for all of these suggestions, i'll have to jack it back up and look at some of these options and start the process of elimination.