My 96 XJ was failed on state inspection for the passenger side tie rod end (on the drag link assembly) not being bolted tightly enough to the tie rod. After pulling the cotter pin to get access to the castle nut, I tried to tighten it and found that the nut and bolt both turn when put under torque. Using a c-clamp to push the drag link assembly and tie rod together makes it much harder to turn the nut, but it still does not come free.
1. Any tips on getting the nut freed up? I have been soaking it in Liquid Wrench and will be taking a hammer to it later to try to free it up.
2. In the event that I can free it up, tightening it down further would put the castle nut too far from the cotter pin hole. Would putting some washers behind the castle nut be fine, or should I look to replace the tie rod end?
Thanks!

are you using and impact gun?

if it has a ton of play just replace the end.

Soak the tie rod and nut and let it sit for 30 min - 1 hr. Then, take a wrench to turn the nut and another tool such as vise grips to hold the tie rod stationary while you tighten the nut.

Replace the TRE. I've had them like this before, where you couldn't loosen the castle nut - the stud just spins. If you can't get it loose with the vise-grips, like jake92 suggested, a sawzall works nicely.

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