Carlos,
Are you sure about this, or have the internal seals on the ram just blown out? Its pretty typical for a 930 thats being used for loader duty to have those seals blow out. There isn't much on the column/box to seize up, and I've never heard of it before actually. Pull the steering rod off the ram (its on the front of the ram on a ball joint) by removing the crown nut and using a pry bar to lift it off. You should then be able to turn the wheel just fine. If the wheel will turn, then its simply the seals on the ram, which can be rebuilt. If you can do it yourself, the seal kit is available for about 20 bucks. If you don't know how to rebuild a ram, it'll cost you about a hundred bucks.
As an aside, if you plan to use your 930 for many, many moons for serious loader work, find the back axle from a self propelled combine. Something off an 86/8900 White would be ideal. Mount the axle in the stock location, pull the hydraulic flow divider off the bottom of the combine steering column and put it on the stub shaft of the 930. Then extend the hoses from the power steering pump on the 930 to the flow divider. You'll then have full hydraulic steering on the 930 and never have to worry about that power assist ram giving you grief again. You should be able to find these parts at a wrecker for next to nothing.
Rod
