Sorry this is so long. I posted in 6.0 forum with no luck, so thought maybe someone here may have an answer. Ok I know this has been beat to death, but here goes. My steering has been all over the place, also will catch left and right, and will not center itself. I fairly sure it is the steering box as I know the u joint on drivers side is good, and just replaced that hub assembly. My question is I an really tight right now, am starting a job this week so things are gonna get better, but gotta be able to get to work and that thing is tough to drive with what it is doing. I have a 99 f350 as well but I believe it has the 32 spline gear box where the 04 has the 36. The 99 is down right now for awhile so, I was wondering if there would be any reason why I could not use the box off of it for a quick fix since I will have the pitman arms for each size? Hate to do it that way but if it will work I'm kinda limited on options at this moment. Thanks in advance for anyone that chimes in or may have an answer!

 

REALLY sounds like a seized universal joint... did you happen to check the RIGHT side? I recommend raising the front end off the ground and disconnecting all steering linkages and exercising everything to look for seized ball joints. This will make your steering feel unstable and constantly have to correct giving the non centering feel. If you don't visually see a problem with the universal joints, the best way to check them (other than with the shaft out and on a workbench) is to engage the 4X4 hubs, with the tie rods disconnected from the knuckles, move the knuckles left and right with the universal joint lined up horizontally, and then rotate the shaft 90 degrees and repeat. A tight universal should be pretty easy to detect with this method. I would be absolutely sure about all of that before even thinking about condemning the steering gear.

To answer you question about the gears, it depends on the parts. If the gear bolts in that is half the battle. A pitman arm change and a lower steering shaft change may also be required. Personally, I would look for the correct part though I understand that there have been discrepancies with newer model year replacement gears.