Upper Wishbone bolt came loose, why?

[Sunray]

Van was starting to make some horrible noises front left side under braking and on full lock yesterday and I was about to hit the M25. Fortunately I passed an open Kwik fit, swung it in to ask if they could check it was safe to drive. They showed me the problem and did it up again and checked it all out.

Tightened it as hard as it will go and added a locking washer and Loctite thread locker just to make sure. They did it for free. Its fine now. Gave the guy a tip as that saved me lots and lots of hassle.

Mechanics who had replaced all the bushes who I understandably complained to, said I need a new nut and bolt as he did it up as tight as it would go? From my perspective, apart from it being under tightened, how would a bolt come loose like that? I can understand it breaking from tension or wear over the years but a bolt wearing out causing it to come loose? Its not like its been done up and undone regularly over the last 25 years. I have my doubts on his statement.

Thoughts

[waltraud]

He's covering his back.

[KamperKev]

Mine have a habbit of working a bit loose. I thread locked and put on a second bolt on each side.

[Simon Baxter]

They are a 10 grade nut and you have to properly swing on them.
Lesser nuts will strip.