I think the OP has already found his answers, but I want to clear some things up for future readers that may come across this thread.
My truck is a 2007 Ranger with Torsion Bar suspension
I was looking to swap my front suspension out, new control arms knuckles etc. looking through rock auto and seen theres aluminum 4WD steering knuckles
look the same as 2WD except you need a hub instead of a wheel bearing. Ive wanted to do a bigger brake swap on my truck and having a hub would make it much easier than the spindle style of 2wd. I've seen people ask this question before for people going from coil to torsion spindle/knuckles not torsion to torsion 2wd knuckle to 4wd knuckle so they would be more or less the exact same.
Is there any serious issue that can occur running a 4wd knuckle+bearing combo with out a CV axle ?
Would i just be looking maybe for a cap to cover the inside of the bearing?
I like the idea of going to lighter aluminum knuckles and having a bigger selection of slide on routers to do a 13" disc conversion with since the 12" sport track mod wont work with the 2wd torsion spindle/knuckles.
I feel like those aluminum steering knuckles are not for a Ranger, regardless of what the listing says. I've heard of 2004+ Explorers having aluminum, but never a Ranger. I would like to be wrong about that, those would shurely be a lighter than the stock cast iron pieces. The strength of steel would be advantageous for an offroad truck, but for a street truck the weight savings might be worth it. I'll have to do some more research on this in the future. I was already planning to upgrade to the 12s on my 99 4x4.
Regardless, as said it isn't your best option. While you could directly bolt the 4x4 steering knuckle to the upper and lower control arms in your 2wd torsion bar Ranger, as others mentioned you would need additional parts (stub shaft) to keep it from coming apart. You'd also need the unit bearing hubs and what ever else is required to keep the stubshaft in.
The Explorer Sport Trac 2wd knuckle will bolt directly onto your 2wd torsion bar Ranger. This would be the easiest solution, but its only 12". Unmount caliper and bracket, remove Ranger knuckle and rotor, install Sport Trac knuckle and rotor, install caliper and bracket. It even uses the same caliper, so you don't have to mess with the hydraulics.
Another option that may be worth checking out is that these guys were planning to do a kit for SLA Rangers based on 13" Rotors and 4 pot brembos from the Cadallic ATS.
https://www.facebook.com/SSEngineeringLLC
The 2wd and 4wd knuckles are similar, but not identical - the ball joints are different. So, you really need to swap the upper A-arms to change from 2wd and 4wd knuckles (I can't remember the exact issue with just installing 4wd ball joints, but there was some problem there too. Although that might have been cost of ball joint was more than whole A-arm...)
The other item to be extremely careful of is the unit bearing. It needs the front axle shaft bolted in to hold it together. Without axle shaft, the bearing falls apart and your wheel leaves the truck. There are couple solutions for this: Option 1: Jeep made a stub axle for there 2wd Cherokees which will install in Ranger unit bearing. Option 2: Take the axle from 4wd (all you need is CV out) and install (if you have access to lathe <recip saw for crude version>, you can trim down to just the stub you need.).
Edit: Corrected - it is just the upper A-arm which needs to be the 2wd one.
First "paragraph" won't work. For starters, my understand is that the 2wd coil spring control arm won't fit the frame mounts on a torsion bar truck. I haven't tried myself, but it has been an aggrevation for people trying to lower Edge Rangers, no upper control arms that will fit the frame. An agrevation I'm likely to share in the not too distant future. Torsion bar and coil spring upper control arms use different size ball joints and, while they do exist in the aftermarket, most Ranger upper control arms do not have repalceable balljoints. Even if you happen to have the repalceable balljoint arms, I think that the body diameter of the joints is different. None of that really matters since the 2wd torsion bar suspension uses the same upper and lower control arms as the 4wd suspension, and the knuckles will physically bolt in place of each other.
As for the rest. Thank you for stressing that fact to the OP. As the link you later provided shows, it will not end well. While not the best solution for the OP, it is an option and it's a great "trail fix" to be aware of though is you happen to end up with a broken front axle.
nope theyre the pinch on top like the 2wd and 4wd torsion knuckles
View attachment 89418
It is shaped like a Ranger knuckle, but I'm still not sure. It would have to be for 2003+ 4x4 Rangers or Sport Tracs up to 2006 (or when ever they got the 4.6), because that is when the Ranger upgraded the rotor size and the Sport Trac swapped over the the existing explorer components.
4x4 Parts still won't be the right options for you unless you can get them dirt cheap. Meaning knuckle, rotor, CV axles, and every other part required for practically free. I stand by the idea that the 2wd sport trac would be your better option.
Please trust those of us who have done it
You need to swap upper ball joints (or upper control arms) and then you can bolt any 2wd ranger spindle directly on. (4wd upper ball joint is slightly larger diameter) And yes RockAuto, etc occasionally get it wrong.
https://www.therangerstation.com/forums/index.php?threads/4x4-without-front-axles.199289/ Another example of someone doing it.
@2Krngr did a nice job machining outer axle stubs.
Not a good idea to say trust us then provide bad info. Again you do not need to swap control arms to bolt on a
4WD knuckle, and a
2WD knuckle isn't going to fit the frame. You can however bolt a
2WD SPORT TRAC knuckle directly to your torsion bar suspension.
That link is definitely a good one to read for many reasons.
If you have torsion bars, you already have the 4x4 suspension, they did that on the Edge and a few other models to get the higher ride height, so you have 4x4 brakes and everything except the actual front axle spinny bits and transfer case and such...
Correct. The Edge (2wd torsion bar) Rangers had the 4x4 suspension with a "hybrid" knuckle. Yep, Ford actually produced a separate knuckle just for the Edges. Ok, not really. That's what a lot of people seem to think, but actually they only produced the SLA Explorers with torsion bars but had both 2wd, 4wd, and AWD versions of it. The "edge" knuckle actually existed before the Ranger got SLA and the Sport Track was created.
Incorrect on the brakes. All SLA Rangers used the same caliper whether 2wd or 4wd. The rotors were different. Remember where I called the knuckle a hybrid above? Well it was a mix of the 4x4 mounting points and the 2wd spindle. While it mates to the torsion bar control arms and caliper, it uses the bearings and rotor of a 2wd.
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Now we just need to confirm if the listing is correct. Once I have some other projects squared awar I might order a set and see what they really are.
