Strut Rod Bushings poly vs rubber

JGC403 said
I have seen a couple of threads on here about people complaining about the poly lower control arm bushing and the Lower control arm moving around on the pin. I didn't understand how they could have a problem it shouldn't go anywhere. The lower control arm can't move forward because of the K-member and shouldn't be able to move back because of the torsion bar. I just can't figure out how they were being installed wrong. I'll have to get some poly busing for myself and take a look at them.
I'll give the PST strut rods a shot. I'm trying to make this car handle as good as it can get.

There are a couple problems that come up. The biggest one is how the poly bushings fit into the outer shells. The tolerances on the outer shells aren’t great, so, if the poly bushings are loose in the shells it can cause issues. But that’s part of a proper installation, the poly bushings should be tight enough in the outer shells that when you install the LCA pin it takes some effort. Not a press fit, but a tight fit.

The other thing is using stock strut rods. The stock strut rods are a “one size fits most” operation. Those big fat rubber strut rod bushings are necessary to make up for the loose factory tolerances. But they let the LCA flex back and forth on the pin. Which kinda works with the factory rubber LCA bushings. But with poly LCA bushings there isn’t much flex at the LCA bushing, so the flex at the strut rod translates to the LCA sliding back and forth a bit on the LCA pin. And if the strut rod isn’t quite the right length it adds to that problem.

Which is why I use adjustable strut rods and greasable LCA pins. The strut rod can be adjusted to suck the LCA right up against the bushing on the pin, and it won’t move much because there’s no slop in the strut rod. And the greasable pins fit the poly bushings better, and allow you to keep them greased so you don’t get the “poly squeak”.

You can use adjustable strut rods just fine with rubber LCA bushings, but I wouldn’t use stock strut rods with poly LCA bushings. And I don’t think poly LCA bushings are a good idea, because if the strut rods aren’t exactly the right length they’ll cause issues because there’s no give to make up for the tolerances.