So I have a 2009 g37xs, when I was replacing both front wheel bearing I came across one of the 4 17mm bolt from the back of wheel bearing hub assembly and none of the other 3 look like that?

 

Looks like it may have been over torqued. It looks stretched to me.

 

^like what he said. thats right on. it was over torqued. go and get another before it breaks.

 

Yeah, stretched bolt. Someone used an impact gun and over torqued the hell out of it. Or used a breaker bar and over tightened it.

 

Oh I changed it for sure but I was just surprise that I have been driving with it since I bought the car.
wait a min does that mean they replace the wheel bearing within the first 3 years 72 000 km they had it and I changed it 5 years after I had bought it in 2012?? wow that's Impressive.