Hello all, been a bit since Ive been around.
The steering box on my truck decided to start making a mess of itself, pretty sure it was bad from the get go OBS donor truck. Anyhow I tore
into my extra that had been in the dually, without a hood for years. Thought I would rebuild and swap it, but no go there. It was pitted from
rust inside.
Instead of just rebuilding the one that was in the truck. I decided to go see what the one in my NBS 2500HD donor looked like. Why not complicate things more. While still covered in oil, and probably leaky also, which will then result in me taking it all back apart and again, it did have a newer reman stamp on it. But my main purpose for even giving it a look, was I remembered the NBS used a universal joint, instead of the rag joint.
Turns out the OBS 3500 trucks, and a portion of the NBS 2500HD trucks used the same steering box. The only difference being the DD input shaft on the NBS, and the output shafts only have three flats instead of four on the OBS. From my visual inspection, and mockup so far, the pitman arm is exactly the same otherwise. A person could swap the output shaft between the boxes, but I'm going to go ahead and run the NBS pitman arm for now.
Some photos of the boxes, and part numbers. The rusty one was the 98.
I had a bad steering shaft, and a pretty minty one. The sizing on the NBS tube looked about like the sizing on the OBS intermediate tube. So I broke my bad one apart
to check it out. Turns out they fit pretty good. There was a small stop on the inside of the NBS tube that I had to hand file, but slid right in.
Am considering two options. I can murder the nice one. And section them together in the larger black tube area. They appear to be the same size. Which then I have to watch the heat to the plastic.
The second option would be to plug weld the intermediate tube into the NBS tube at the old bolt holes, and weld along the top. There ends up being a problem that puts the steering wheel 90 degrees out going this method though. They are clocked wrong. Though if I go this way, I might be able to free and reuse the parts from the bad shaft. Technically I could do a cut to clock it correct also. But all this babbling isn't really whats this is about.
The 3500's don't have airbags, so a person could just recenter the wheel, but I'm also going to go aftermarket in my case, so the clocking isn't that big of an issue. This also may be a 3500 only mod. As GVWR ratings come into play on what steering box you have. I don't know what all will cross reference, and I wouldn't recommend any modifications of sorts, if you dunno what you're doing, and your welds are boogers that fall apart.
I still have yet to complete the task, just thought I would throw this info out there. Maybe help someone someday. Aftermarket shafts are not cheap, and gearboxes get leaky.
Edit: Linky to some OBS box info https://leepowersteering.com/pages/how-to-identify-gearbox
The steering box on my truck decided to start making a mess of itself, pretty sure it was bad from the get go OBS donor truck. Anyhow I tore
into my extra that had been in the dually, without a hood for years. Thought I would rebuild and swap it, but no go there. It was pitted from
rust inside.
Instead of just rebuilding the one that was in the truck. I decided to go see what the one in my NBS 2500HD donor looked like. Why not complicate things more. While still covered in oil, and probably leaky also, which will then result in me taking it all back apart and again, it did have a newer reman stamp on it. But my main purpose for even giving it a look, was I remembered the NBS used a universal joint, instead of the rag joint.
Turns out the OBS 3500 trucks, and a portion of the NBS 2500HD trucks used the same steering box. The only difference being the DD input shaft on the NBS, and the output shafts only have three flats instead of four on the OBS. From my visual inspection, and mockup so far, the pitman arm is exactly the same otherwise. A person could swap the output shaft between the boxes, but I'm going to go ahead and run the NBS pitman arm for now.
Some photos of the boxes, and part numbers. The rusty one was the 98.
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You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
I had a bad steering shaft, and a pretty minty one. The sizing on the NBS tube looked about like the sizing on the OBS intermediate tube. So I broke my bad one apart
to check it out. Turns out they fit pretty good. There was a small stop on the inside of the NBS tube that I had to hand file, but slid right in.
Am considering two options. I can murder the nice one. And section them together in the larger black tube area. They appear to be the same size. Which then I have to watch the heat to the plastic.
The second option would be to plug weld the intermediate tube into the NBS tube at the old bolt holes, and weld along the top. There ends up being a problem that puts the steering wheel 90 degrees out going this method though. They are clocked wrong. Though if I go this way, I might be able to free and reuse the parts from the bad shaft. Technically I could do a cut to clock it correct also. But all this babbling isn't really whats this is about.
You must be registered for see images attach
The 3500's don't have airbags, so a person could just recenter the wheel, but I'm also going to go aftermarket in my case, so the clocking isn't that big of an issue. This also may be a 3500 only mod. As GVWR ratings come into play on what steering box you have. I don't know what all will cross reference, and I wouldn't recommend any modifications of sorts, if you dunno what you're doing, and your welds are boogers that fall apart.
I still have yet to complete the task, just thought I would throw this info out there. Maybe help someone someday. Aftermarket shafts are not cheap, and gearboxes get leaky.
Edit: Linky to some OBS box info https://leepowersteering.com/pages/how-to-identify-gearbox
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