WOW - You are lucky a spark did not ignite all those magnesium shavings from the wheel! Pretty car.
In order to re assure 355 owners that typically these front ball joints are very strong when at correct torque, the one that remained on the lower arm when the hub shown detached from the 355 in an accident, looked as good as new when I checked it, the hub failed first in that scenario. I have a used front ball joint somewhere, when I find it I will take a pic to see how normally waisted the shaft is at the point where it attaches to the ball. Image Unavailable, Please Login
@PAUL500 ...that's where my head is at...it worked it way loose and that play eventually caused the failure. Will be checking and rechecking the torque on all suspension components before going back out on the road.
Glad your safe! That’s some interesting pictures. Been a long time since I did metallurgy, but I’d go with a fatigue failure from lack of tension. Be good to get a metallurgy guy to have a look at that.
that narrowing/waist of the shaft is where mine failed. Thanks for the pic and all the responses. Here's a link to the torque specs for various parts of the 355's suspension and braking...I'm about to go to town with a torque wrench. https://www.the355.com/showworkshoppage.php?page=128&volume=2&title=Tightening%2520torque%2520summary%2520table
While you're under there, look for anything that looks like accident damage. Maybe the body shop forgot to tighten a nut. sjd
Sorry to hear about what happened (and glad no one was hurt), but an interesting thread for sure. I was checking your car out at LRP on Sunday; a rubino 355B with 6000 miles isn't something you see often! Hope you're back on the road soon.
So just got the replacement ball joints..went ahead and pulled the passenger side as well to inspect/replace. noticed something odd…the lower ball joint reciever on the passenger side is 17mm, while the drivers side is 23mm. Upon closer inspection of the two old ball joints i notice there is a collar/bushing on the driver side ball joint that failed….and none on the passenger side? The collar is sized on the remaining shaft of the ball joint. Anyone know why there is a collar on the driver side? Could this be a factor? Did Ferrari used both interchangeably driver side (USA) -23mm - where the ball joint failed Image Unavailable, Please Login Passenger side (USA) -17mm Image Unavailable, Please Login Both ball joints..one one right has bushing to fit in driver side hub Image Unavailable, Please Login ?
Edited my reply as your pics had me intrigued so I went off hunting. Both the damaged and spare hub I have here are circa 23mm, so either the collar is a press fit into the hub and is missing from both of these and still attached to the old ball joints or there were changes during the life cycle of the 355, Next stop is the eurospares website to see if they list different part numbers for the ball joint depending on year, or if they list a collar. A pair of hubs I previously fitted to a car accepted replacement ball joints so either I was lucky to match everything up without realising or there were changes.
In looking at your picture it appears the collar is still in the passenger side hub and the failed side collar is seized to the broken stud of the joint.
No collar on the passenger side..look close and you cans see the machining in the aluminum of the steering kuckle Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login View attachment 2575634
You are probably correct but the failed side also looks to have been machined to properly fit that collar. I also had looked at the parts drawings and nowhere does it show a collar. Weird one for sure.
According to the eurosprares website there were a number of revisions to the knuckles on the 2.7 versions during their life and then 2 types for the 5.2 versions depending on whether for Bosch abs or Teves sensors fitted. The two in my pics are from a 96 spec 355 Interestingly there is only one part number for all versions in relation to the ball joint, so I guess it just means the threaded part slides further up depending on which hub is fitted/width of hole in the hub. No inserts listed for any of the hubs. Also interesting is that eurospares sell a pattern ball joint which has a castle nut! Sounds like you have one spec hub on one side and a revised version on the other, probably just using up stock at the time when it was assembled. The hole in the hub pic does look smaller on their website as if a collar is fitted. Given that all the other significant holes in the hubs do have inserts/collars though it would seem like the hole for the ball joint would also have them. Image Unavailable, Please Login Image Unavailable, Please Login
This is bizarre, it looks like you have 2 slightly different uprights, and rather than source the correct ball joint for each, an adapter was made to fit the same ball joint on both sides - and there does not appear to be enough shoulder on that nut to properly hold the thing together, unless there was a (now lost) washer under it. The odd part is, on a 6000 mile car with no known work in that area, it appears to have been a factory boge, but you'd think they'd just grab a matching upright or another ball joint as opposed to machining an adapter bushing....What year is the car?
Pete, there is only one ball joint available for all the 355s its been superseded though twice for some reason, but its the only one available for all the cars Image Unavailable, Please Login
If you look at the picture Paul500 posted of the hub the three holes do look like there is some form of pressed in collar (especially in the hole at the top of the hub). Could account for there not being any separate listing for it in the parts manual. Could it be to prevent seizing of the stud to hub due to different metals since the joint is a replaceable item? Just speculating.
There is a collar inserted on the wheel hub for the lower ball joint, upper ball joint and the steering tie rod. In the pics the OP posted the sleeve is still in the steering knuckle and the broken ball joint had the sleeve still on the shaft. When I removed my lower ball joint with a press one of the sleeves came out the other stayed put. I have my steering knuckle out right now and the upper replacement ball joints came with new sleeves to press in.
Looked again and 99.9% sure there is no collar on the passenger side. zoomed in on the passenger hub and you can see the machining on the aluminum goes all the way to the hole for the ball joint. if it had a collar..that machining would terminate at the collar. Image Unavailable, Please Login Also strange how the supplied nuts are different. The original had a broad shoulder that fits the recess on where the ball joint but goes. The new lock nut doesn’t have a shoulder and is barely wider then the opening where the ball joint passes thru the hub Image Unavailable, Please Login also..why the heck do these old ball joints narrow just below the threads. Seems like an obvious weak point. Image Unavailable, Please Login
Could be that the collar is inserted before machining. Are there machine marks on the collar that came out with the broken ball joint?
Also looked on eBay and see two different designs with same part number… with sleeve for lower ball joint (my drivers side) https://www.ebay.com/itm/300915216796 without sleeve for lower ball joint (my passenger side) https://www.ebay.com/itm/291838234325 Don’t want to reuse the same sleeve..so looks like i need to get a new knuckle without sleeve. this crap would not fly with the Germans..but maybe the brits.