I'm converting my 07 XJR to Arnott coilovers.

On the drivers side front, I am unable to loosen and remove the upper a-arm (wishbone) ball joint nut so that I can separate the upper a-arm ball joint. It looks like the nut is 'frozen' on the stud and the nut is not turning. Instead, the entire stud itself turns when I try to loosen the nut. The stud just turns now when I tighten or loosen the nut with a wrench. I am unable to get the nut off and I cannot tighten it.

I cannot separate the upper a-arm (wishbone) ball joint so I cannot continue with this wheel conversion.

How can I get the frozen bolt and stud off of the existing wishbone so I can separate the ball joint? Will I have to hack-saw it off?

It looks like I will now have to replace the upper a-arm (wishbone) on the drivers side. The replacement part looks like it comes with the bushings and ball joint. Is that correct? Since I'm already removing the shocks, should I go ahead and replace the passenger side wishbone as well?

I've seen on this forum that 07 Lincoln LS upper control arms might fit on an 07 XJR and would work in this situation. Can anyone confirm if that is true?

Any insights, tips, experience, help, etc, would be greatly appreciated.

 

You can buy a thing called a "nut splitter". This little device goes round the nut, and on one side has a screw in cold chisel that is screwed into the nut until it splits.The nut can then be removed.

https://www.toolstation.com/shop/p80...wA8X_-QdNfd5aq

 

Thanks Fraser. I didn't know about nut splitters and it looks like there are plenty available so I'll do some research. It's an 18mm flange nut so I'll have to see if a nut splitter will work on a nut like that.

There may be enough room now to get a vice grips on the stud just below the a-arm and see if the nut will come off of the stud if I hold it. The new a-arm should have a new ball joint.

 

Did you use a hex allen key to hold the stud? You need to insert the hex allen key into the end of the stud to hold it then turn the nut. If you don't use the allen key you'll turn the stud and nut all day long with out the nut ever coming off.

 

Thank you JagsteRJX. I didn't know an allen key was needed and none of the installation manuals or videos I saw mentioned it. It may well be in a post in here somewhere but I didn't see it or find it. I checked and sure enough, the hex key hole is there and my key fits. Now I can proceed.

And you're right, you can turn that nut for a long, long time and it just ain't coming off without the key.

Thanks again!

 

In most cars I have owned with this arrangement, the hex socket corrodes to the point where the allen key will slip in the socket and not restrain the stud from turning. And then I have had to use nut splitters or other means to get the nut off. You may be lucky, or maybe not.

 

Heat works

 

I had one of the hex slots strip out on me when I was changing the front suspension last week. As I was already going to replace the upper control arm, I used an angle grinder to cut the nut off.

 

Mine had a thread locker that I used a torch to melt off and the nut came right off with no problem��

 

I had a hard time with mine too. Ended up cutting them off and using Lincoln LS replacement arms.
Jaguar XJ8 Coil Conversion - Parts and Projects