33 GTR Broken front wheel knuckle

[believer]

Hi guy. My front wheel knuckle broke on me just before I hit the track. It’s where the tie rod bolts onto the knuckle. I do have bump steer rose joint tie rod ends but I didn’t hit anything and I do not climb ripple strips on the track, it snapped off when I was doing a three point turn in the carpark. 
Has anyone had the same experience?  This is my second one in two years but in the other side. The car has extremely low kms and it’s only tracked 3-4 times a year. 
Any thought??

 

[Duncan]

We have a lot of posts on SAU from over the years, I've never seen an upright snapped at the steering arm.

 

[GTSBoy]

The fracture pattern shows the force was a moment applied in the vertical plane (ie, the outer end of the steering up was being pushed up or down). I guess up from a cursory inspection.

This would suggest one of a couple of things.

1. Bad day at the foundry. I consider this unlikely, because I would consider it unlikely that both the left and right uprights on your car were made on a single or very rare bad day. Far more likely to come from different days, and therefore there should be many more reports of these failures.
2. The people designing these bump correction tie rods are not considering the change in direction that forces are applied to the steering arms. Again it would seem unlikely as there should probably be more reports, and the steering arms are approximately square in cross section.
3. You have been hitting things with the bottom end of them.

Or a combo of all three? Plus other possibilities/factors?

[Dasmbo]

Never seen this happen twice i would guess parts taken beyond manufactures specks if it were me i would have the next knuckle joint shot peened to try and make it stronger just like you would have your con rods shot peened 

good luck with it

[hardsteppa]

I had this happen earlier this year. R33 gtst, different knuckle but same failure.

[R32 TT]

Just had this happen to me too.  R32 GTR.   Also broke "just before going out onto the track" - someone up there is looking out for us...

Very scary since I was about to do a narrow street course with zero run-off and curbs everywhere.

Many people on here upgrading to billet uprights and R35 bearings?   Or buying new OEM knuckles? 

I am not keen to replace with another s/h 30 year old fatigued part.

[Duncan]

Interesting. I still think they are the result of impact damage somewhere along the line, but clearly lightning has stuck thrice!

I've still got the original ones on my race car and they have had some hard work.