Hi,
Just got a 2008 JKU. I'm going through it right now to make it safe and reliable. it was a mess, but I'm making good progress.
I'm in the middle of replacing all the ball joints, and all tire rods.
I have Moog joints. I have the new ones installed.
The problem I'm running into is the Upper joints, on both sides will not seat all the way into the knuckle. I removed the new upper on the right side and put the old one in for a test and the old one fits like it should. The new one on the left side stops with about an inch to go. That's after tightening the nuts.

Old, upper BJ on Pass side

 

that looks right. the new one just doesnt have that boot on the bottom. but i wouldnt use moog ball joints personally.

 

Yep, you are right. It was the lack of a boot that was throwing me. Took to boot off the old one and it too fits about the same.
Thanks.

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