There have been multiple failures of the early style Magnum Force K members. Worse than that in my opinion is their customer service, as the guys with failures were generally not supported by MagnumForce.
Some of their other parts are fine, but with HemiDenny and RMS out there I’d never even consider a MagnumForce K member conversion. Especially not an early one.
I don’t think I’ve ever seen someone that had an issue with the tubular UCA’s for the torsion bar suspension. I have a set I bought used, they’re good parts and I didn’t have any issues with them. MagnumForce does sell some decent parts. Their K members were the issue historically, especially that earlier design. Well, and their general lack of customer support. If all you do is point and click something on their website and it happens to be in stock it’s not a big deal. If you need actual customer support, not so much.
With all the other options out there now I’m kinda surprised they’re still around.
