This. The appears the fractured pin ran out of threads. Whether that's a design flaw with the length of the pin or a problem with the K member I'm not sure, but based on where it fractured that's what happened.
As far as the torque specs go, I know that Firm Feel greaseable pivot pins get torqued to 100 ft/lbs. I have greaseable pivot pins on all of my cars, with tens of thousands of miles on them between them, and no issues whatsoever.
I would call Hotchkis. They ARE a reputable company. I have some of their parts on my Challenger, and all are well made. I did have an issue with the heim joints on my Hotchkis UCA's failing after about 7k miles, and after talking with Hotchkis they replaced all of them at no cost to me. I would definitely talk to Hotchkis. The manufacturing process is not 100% perfect, it could be that there was a metallurgic issue with the pin as well. And that could mean that there's a "batch" of pins with issues. If that's the case, Hotchkis needs to know about it.
You're wrong. About all of it. This isn't the first time you've posted this, nor is it the first time I've responded.
The bonded rubber of the OE pivot pin bushings DOES NOT secure the LCA. No engineer worth his salt would create a design that required rubber bonding to keep a lower control arm from moving fore/aft. It's simply not designed for those kinds of loads, and is not capable of supporting those kinds of loads, period.
The torsion bar does keep the LCA from moving, but only within a range. The torsion bar can slide back and forth a bit in the socket, but even with the torsion bar all the way back the LCA can't come off of the pin. When the rubber bonding of the rubber LCA bushings fail, as it often does, it is in fact the torsion bar that keeps the LCA from falling off the car. I know this for a fact because I have seen LCA's fall off the pins after the torsion bar and strut rods are removed, because the stock LCA bushings were shot.
It is in fact the job of the strut rod to locate the LCA fore/aft. That is in fact it's only purpose, and the reason that they were included in the design of the suspension. They serve no other purpose. If the LCA was positively located by the LCA bushings, you wouldn't need the strut rod.
In the stock system, the strut rods are a generic length, and have a bit of play from the thick rubber bushings they use at the K frame. If installed properly, the rubber LCA bushings maintain their rubber bonding to the steel inserts, and between that bonding and the additional give in all of the rubber bushings the LCA is located within a range small enough for a decent alignment. It's not perfect, and if you think there's no play in the LCA fore/aft you're mistaken. If you removed the strut rod from the system, the rubber bonding would fail in short order and your LCA would travel fore/aft with the torsion bar, as much as the torsion bar can move in the socket.
When using a poly LCA bushing there are several changes. The poly insert isn't bonded to anything, although it should fit snugly to the pivot shaft and into the steel insert in the LCA, to the point that it should actually require a light press to install. If it doesn't, the stock shell is worn out or too large in its tolerances, or the bushing is undersize. This is actually the issue with the poly bushings. The stock steel inserts are not all the same size, and can be damaged when the rubber wears out and the pin starts moving around in the bushing. Because the fit of the poly bushing can vary, so does the ease with which the pin can move in and out of the K and LCA. The poly bushings also have less give in the material, which means when using them the LCA must be more accurately located. Since the stock strut rods were generic they are NOT a good choice when using poly bushings. Adjustable strut rods should be used to more accurately locate the LCA. This also solve the issue of the fore/aft movement on the poly bushings. Even with a light press, the LCA can move more easily against the poly bushing than with the rubber bonding of the originals. Using an adjustable strut rods solves this issue, as it eliminates the additional play of the rubber strut rod bushings and allows you to more accurately locate the LCA where it needs to be.
There is nothing really wrong the design of the poly bushings. They do depend on the tolerances of the steel bushing shells in the LCA, so they aren't the best solution out there anymore (BAC's Delrin bushings are much better). But that doesn't mean they won't work if you take the time to install them properly. And there is nothing wrong with the greaseable pins either (at least in general). I have had poly bushings, greaseable pins, and adjustable strut rods on my street driven cars for 10's of thousands of miles. I've had adjustable strut rods on my cars for over 80 thousand miles combined now. When properly installed, the LCA does not move fore/aft on the pivot pin or poly bushing. Given that I have less than a 1/2", and in some places less than a 1/4" of clearance between my tires and the hard parts on my cars (frame, fenders, braces, etc) I would know immediately if my LCA's moved much in any direction, as my tires would start rubbing on the body/frame of my car. That's true on my Challenger and my Duster.
Your LCA's move around on your car because your installation was incorrect in some way. The bushings might be too loose in the shells, or the strut rods are the wrong length, or the K frame mounts are worn out, but something isn't right. Poly bushings do not function the exact same way as the OE bushings did, and you can't expect them to. Other considerations have to be taken into account, and while they aren't mandatory adjustable strut rods should really be used with poly LCA bushings. Also, because the shape of the poly bushing is different, the shoulder on the LCA pivot pin should be different as well. It is different on most of the greaseable pivot pins because they were designed for use with the poly bushings. If you re-use the stock pivots, the shoulder on the pivot isn't quite right for the poly bushings. You wouldn't install a high lift cam in your engine without the proper valve springs or rocker gear, and by the same token you shouldn't expect the poly bushings to work as intended if you don't make some additional suspension upgrades.
