When the steering has a significant amount of pressure built up there is a noise like clicking or popping which is emitted from the front end. The noise also occurs when driving down the road with normal turning, particularly in slow corners like when pulling into or out of a junction.

I recorded the sound by applying pressure to turn the wheel when it was dug into a hole a bit in the drive (noise starts around 24s, really audible around 37s): .

Most of the reviews I have read regarding noise from the steering system indicate that the intermediate shaft or the column are the likely causes. I have no noticeable play in the lower column where the Rock Solid Steering Fix bushing would go, nor is there any play in the rag joint or U joint of the steering shaft. There is some side to side play in the middle of the shaft at the splines. When the truck is off, the shaft can be rotated about 1/8th of a turn in either direction. The wheel in the truck and the U-Joint against the box both rotate smoothly together when this happens.

Since the issue occurs when the wheels or steering wheel aren't actually moving, but are just held with pressure on the system, I am thinking that it cannot be an issue with the linkage, correct me if I am wrong. This leads me to suspect either the gearbox or the pump. Any ideas?

Recent repairs:
~2000 miles ago the track bar was replaced and the truck was aligned. The belt, tensioner, and several pulleys were also replaced at this point.
~3000 miles ago the drivers side axle universal joint was replaced.
~7000 miles ago the steering box, both steering hoses, all tie rod ends, all ball joints, track bar, passenger side hub, front calipers and lines, and quite a bit more was replaced.
~7500 miles ago the drivers side hub was replaced.

 

so that horrible banging noise is happening as you apply turning pressure to the steering wheel?

are you actually turning the wheels, or just applying pressure?

do you think its coming from the engine bay or from the front end parts?

i'd start by putting about a 2 foot long pipe to the power steering pump and putting my ear to it like a stethoscope. be very careful of moving parts and the 12v positive terminal. use pvc pipe if you have it.

 

I wish I had a piece of pipe or a stethoscope, as I've thought about doing exactly that, but I don't really have what I need. I also cannot see the linkage as I turn the wheel and I don't have a second person to turn the wheel for me. I did at one point have a friend turn the wheel in a parking lot, I did not notice any play or unusual movement from the linkage.

The noise occurs when the wheels are turning, but it also occurs when the wheels are motionless but there is pressure in the system, either when it is at the limit turned all the way in one direction or when there is something against the sidewall preventing it from turning, like being dug into a hole.

In the video I took, the wheels are not turning at all. I simply grab the wheel and pull it (about 1/2 of a turn) until the pressure is fully loaded up. the wheels had dug into a hole.

Bear in mind that while this noise occurs, the truck will still turn. With the wheel loaded up, if I had turned it further the hydraulics would have overpowered the mud and gravel of the driveway against the sidewall and the tire would have turned. It doesn't appear to prevent it from functioning, but my fear is that if it is mechanical in any nature that whatever is broken is going to go at highway speeds and cause a major accident. Loss of power steering would also suck, but not quite as catastrophically.

I also forgot to mention how this all happened. I pulled to the side of the road on an unplowed road to let some idiot in a station wagon go by (they were going downhill and in a wagon so I was nice in my big beefy truck to give them the road). I amazingly found the gigantic ditch on the side of this windy, unmaintained, mountain road and realized that I was quite stuck. 4WD was not enough to pull me out of the ditch, but I could drive forwards and backwards in the ditch. I tried building momentum, it didn't work, and I managed to build up enough snow under the truck to float both axles and get properly stuck. Some digging later (with my ice scraper, no shovel) and when I hopped back in, the noise started when there was pressure on the steering. I thought it was just something in the snow against the front drive shaft (I was steering and trying to get the truck to move at once). I managed to get the truck out by backing up and swinging the front end up the opposite slope into the woods, then backing onto the road at a 45 degree angle (did I mention the other side was about a 50ft drop?). Anywho, it's made the noise off and on ever sense, sometimes while driving, sometimes while stopped, and sometimes the noise will go away even when held against the limit with full pressure.

The steering fluid is full. I though maybe bubbles in the fluid? Needs to be bled perhaps? Still no idea though.

 

Replace power steering pump. Flush system REALLY well before you hook the return line back up.