I have determined a pattern to the reported failures of the lower ball joints used with Fiat/Pininfarina 124/2000 Spiders/Coupes. Information had been sketchy as there are MANY different aftermarket products out there. Trying to properly identify what is good and what is bad has been nearly impossible.
Background:
The design of the front suspension has the lower ball joint pointing up. The weight of the front of the car pushes down on the outer casing of the BJ where it attaches to the control arm. The ball and shaft portion bolt to the steering spindle. The car basically hangs from this joint. When the casing of a ball joint fails it can be catastrophic. The wheel and spindle will roll out and become separated from the car. The car will drop to the ground on that side. This is what usually happens when a lower ball joint breaks and you live to tell about it:

THIS TYPE OF BALL JOINT IS KNOWN TO HAVE FAILED ON SEVERAL PEOPLE. IF YOU HAVE THIS TYPE, PLEASE PARK YOUR CAR AND GET THE SITUATION FIXED!

These are two pics of the same style which has failed on several occasions. This is the only type that has repeatedly failed in the same catastrophic way. Look carefully at distinguishing manufacturing marks. There is a depression where the grease fitting is and there are two different punch marks on each of the three sides. Click on the images for a bigger view. Be careful as some are very similar to other styles

I have found several styles that I can not identify by name yet. Some of the image file names give a clue to the manufacturer. Some are pressed steel and some are cast/forged. (I'm not sure about the metallurgic differences between cast and forged) Here are pictures of several of the styles. Clicking on them gets you a larger view. As you can see, there are MANY different types out there. Some look extremely similar to others!

Click HERE for additional pics
Kelly D. from Wine Country Motors has posted MORE PICS of balljoints and A arms.
This lower made by Redaelli has a very clear stamping on the top side which says "NB15A 62".
The uppers have a stamping on them which says "PD11P 62".

Here is another type. It looks like this from the side:

and looks like this from the bottom.



Here is another type. It has the marking "MB Made in Italy". It looks like this from the side:

and looks like this from the bottom.



More to come later as I work on this. If you have any info to share about lower ball joints please email me at thadkirk@hotmail.com
This page is meant as informational only and does not imply the safety of individual parts. Do your own homework.