Have a 68 Dart with a lower control arm pin that does not want to tighten down. I believe these are tapered and supposed to "press in" to the K frame as you tighten it down. Correct ?
The K frame and pin both appear fine with no noticeable wear. Any comments /suggestions/ fixes ??
Thanks

Is the whole pin spinning ?If the lower control arm bushing is bad it could be letting the pin spin.The pin goes through a tube in the k frame and the shoulder on the pin seats against the tube from control arm side.

I had that on one side for mine. It was fine until the last couple of ft-lbs, then started to turn. I was able to sneak a pair of vice grips on the other side of the pin by the LCA to hold. Just put a tiny mark on the pin, not noticeable unless you look for it.

Yes the whole pin is spinning, It's a poly lower bushing so that is not helping. The other side was no problem, locked right down.

Chase the threads on the pin so the nut will go all the way on finger tight.

The threads are fine, the pin begins too spin when one tries to tighten it.
I was under the impression that the the pins were tapered as was the sleeve in the k frame for an interference fit as it is tightened ?

When using those poly bushings, aren't you supposed to put the shaft, (pin) in first, tighten the nut down, by holding the shaft with vice grips, or channel lock pliers.
Then installing the bushing in the LCA's onto the shaft?

Yes the pins are supposed to lock in on the taper. It may still spin while tightening if you use poly bushings. With rubber bushings they wont. Some aftermarkets are made with wrong taper though.

After reading several posts on other forums I ordered new shafts from PST. they are supposed t be about .005" larger. We''l see if they tighten up

Thanks for the inputs

Took the k-member out of my son's Dart earlier this year. It's one that I built many years ago (to Direct Connection specs) before I knew a lot about them. One side had had a pin tube repair done really badly and I couldn't get that one pin tight. The "repair" that had been done by somebody else prevented the pin from fully seating in the tube. The tubes are also not exactly straight. They have a slight taper at the back end...The first and third pics show the taper in the tube. The middle pic shows the poor repair that prevented the pin from seating.

Its tapered so it you give it a whack on the back side with a mallet to "seat" it in the taper it should hold enough to tighten the nut. Note that when using a standard rubber bushing you do not tighten the nuts until ride height is established. With the poly bushings ... who cares !!

Why don't they make the bushings .005" tighter ?!?! Oh, wait, they wouldn't be able to sell you the pins! What a scam!

The bushings weren't the problem, The original tapered shaft that fits into the K member was the problem

Just hold with the vice grip like I said. After I did that to torque spec I went back and tightened again without the vice grip and it was fine.
Mine only started to turn at the very end, not sure how early yours are.
And they can turn with rubber. The inner sleeve is only riding on rubber. While tight, it can turn.

How do you figure that? They'd work just fine in a bushing that put enough pressure on them to hold them.