355 Ball Joint Failure on 6k Mile F355

Here's my thoughts: They fly cut it after it's pressed in. It's likely how they get the tolerance on the ENTIRE knuckle. If they didn't then the tolerance of the flange on the insert would drive the tolerance PLUS the tolerance on the counterbore hole.

sjd

 

or your car's been crashed and no one said anything.

sjd

 

Build date?

 

Undoubtedly all have pressed collars as you wouldn’t be putting those into an aluminium housing without a harder material to press into. Wouldn’t end well.

As to the difference in nuts; the original is far more expensive than a standard 10 cent nyloc nut you can buy from anywhere. Ferrari still sell the originals. They also lock in a different way. Although oddly their call joints come with a bog standard nyloc; guess as a result that they are from a parts bin not specific to Ferrari and fit a whole load of cars and made by somebody else.

www.ferrariparts.co.uk is the website to use.

The only oddity here is why tne origami all ball joint failed; and gnat needs commentary for a metallurgist for a definitive answer.

 

Orangevespa, there is a quick check you can do to see if there is an insert in your good side. Take a good magnet and see if it is attracted to the possible insert collar. The hub is aluminum so if no magnetic draw there is not a steel collar.

 

Possible but -looks- like all aluminum and not a sleeve that was fly cut. Usually you can still see the difference in metal color

 

What a great thread guys......

I would say the collar is a part of the upright, pressed in at assembly of the part.

I would also set forth that , like the wheel stud inserts into aluminum, it's there to strengthen the upright.
I don't think the raw cast aluminum would hold up to the stress of the suspension action, therefore the collar insert.

But it would not be an independent part.

NOTE: I don't own a 355, so therefore don't know &%**, I have had minor impacts over curbing and storm inlets, that totally shattered aluminum uprights on "other fast cars" and am only here, to tell this tale, because like the OP it failed at low speeds after some 150MPH runs!!

 

That would be my theory, pressed in, then a final machining...

 

A magnet won't lie. It looks like two colors to me, but I'm just a guy at a computer looking at pictures.

sjd

 

The chamfer into the stud is part of the machining I think, it happens at the 360 Camshaft Variators also, with tragic results!!


So I 'm gonna duck out, but it's also noted the "castle nut/pin" method of the 348 was superseded by the Nylock hex nut on your new ball joints.
That's an "Accounting department labor savings on the assembly line" decision, IMO, and if the older style castle nuts are available that would be a better assembly, in my mind...but racers like to tie wire everything, ya know???

 

I suspect as posted above this car has an "early collarless" upright at the passenger side, and a later "insert style" on the drivers side.

As to how it got that way, I don't think the Factory would have comingled parts, as there was a reason for the design change...
But I can't see Italy from here!

The aluminum upright failure I experienced was at a VERY low mileage( as I admitted to a miner curb impact) but not that long after in 1994 a poor girl in the same car, went missing, and two weeks later was found upside down in the forest, expired. I suspect she was bombing down an Off Ramp, and a curb impact handed her the same failure, albeit at a much higher speed.

 

Definitely insert collars in the aluminum housing. one is still attached to the ball joint stud. My unprofessional opinion, looking at the fracture, it seems there were cracks in the stud on each side. The steel fracture has darker discoloration on the sides as compared to the shiny metal in the centre, indicating an accumulation of dirt. Could have been cracked (the dark part) for a period of time before letting go. ie; the shiny part. A loose bolt may have cause too much side load movement, cracked the stud , then broke once the force exceeded the the strength of the remaining stud. glad it was not as serious as it could have been.
Those cheap nylok bolts should not be used for a critical part like this. Get some good quality locking shoulder bolts that help spread out the load.

 

You fix the broken side, and life goes on.

You are right though that's not a Repair Order one would keep in the file or include in a sale!!!!
Mine was repaired under warranty, but as my carrier paid it and subrogated against the manufacturer....

I banged the new one on the metal counter and handed it to the mechanic to install!!!


..and was careful with curbs going foreword!!

 

Any of you guys who were asking about the year of the car make any correlations as to when the switchover occurred?

sjd

 

I am sorry to hear about this but it does look like a freak occurance.

I also do not want to hijack this thread but a '95 GTB is Rosso Barchetta with 6,500 miles?!?! Sounds like my dream F355. I would love to see more of it and learn its story.

 

That has been failing for a good while, the outer diameter is totally different to the light grey centre where it finally failed.

 

Agreed on the magnet, disagreed on two colors, and same here

 

Looks like scoring )arrow) and chip (circled). Not something I would expect of a steel insert.

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All depends on what's harder...

sjd

 

I subscribe to the school of occum's razor which States that the simplest explanation is usually the correct explanation. It's likely a previous owner hit a curb or a pothole which weakened or fractured that ball joint and then it was just a ticking time bomb. My old 328....one of the front front mounting forks for the control arm failed and it was determined that it was bent and mangled and cracked because you could tell from the rust....and then it finally failed.

 

Well that's something you don't see everyday on FChat, a red Ferrari 355 Berlinetta.

Looking good.

 

I suppose anything is possible. Not doing the math on anything but just my guess. I don't think it would be possible to hit anything at any speed which would allow the shock/spring assembly to transfer enough force to that ball joint to pull it apart unless it was already damaged or flawed.

To me it looks like abrasion/material transfer on the underside of the nut (edges look a bit hammered)

Without having the parts in hand, my impression is that's more indicative of either -not- being torqued. So enough play in the assembly to pound that part until it eventually fatigued and failed.

OR-

Would also like to see the top of the original knuckle. If for some odd reason the top surface the nut torques against is not square to the bore it would put a bending force into the failed part when torqued.

(Or similarly, nut threads not square to flange)

 

I just noted from the picture that the OP posted of the car that it looks like the front bumper doesn't have a side marker light...