If a control goes bad, can it lead to a catastrophic failure/accident?

 

Yes, if the balljoint pops out, the wheel is no longer connected properly and flops about, causing a loss of control. To see pics that illustrate my point, do a quick google search on "Durango Ball Joint failure".

 

Imagine a front wheel suddenly pointing in a drastically different direction, or worse coming off the car. Imagine this on the highway or at the end of the front straight on your favorite track.

Yes, this is a potential catastrophic failure. A search will pull up a number of threads describing the issue and various remedies.

Good luck.

 

Yikes. A quick search has revealed much. Thanks.

 

Does'nt your car comes with steel A-arms ?
A better alternative is to convert aluminium
to steel arms if your car is pre 87. That's what
I did to my 951 but before install, I seam welded
the steel arms to increase strenght.

 

Actually, in our cars, it's more likely to happen coming out of a turn, on the inside (unweighted) wheel.

As you take right turn, the right side suspension expands, while the left side compresses. If the balljoint is bad, then one of three things can happen on the right:

1. The ball joint pops out of the A-arm, and lands back in the A-arm. Shew - no real damage yet, but read on...

2. The ball joint pops out of the A-arm, and lands infront of the A-arm. You're screwed, but you have a good chance of stopping the car is a relatively controlled fashion - if you're lucky.

3. The ball joint pops out of the A-arm, and lands BEHIND the A-arm. In this case, the right suspension will most likely collapse, and buckle under your car. If you're lucky, it won't rip apart the whole side of your car before you stop.

It is the expansion / compression of the suspension motion when a damaged/cracked A-arm will allow the ball-joint to pop out.

If you track your 944/968, and have aluminum A-arms, these should be checked prior to EVERY event. You can squeeze the ball joint to determine the amount of play, but that still won't help to determine if the ball joint can pop out: it's more difficult to see if the ball join can travel UPWARD if the suspension is unloaded. Replace the A-arms every 3-4 years, or get the aftermarket steel ones.

-Z-man.

 

So, if there is play within my ball joint, #'s 1, 2, or three could occur?

 

Yes.

of the four or five failures I've seen all were lucky and came to a semi-controled stop with minimal car damage, don't be the exception that proves this wrong, have them checked, replaced or up-dated

 

Respectfully, I think this is overkill. If you keep your car in good working order, and do periodic inspections on them (which I do when I am tinkering on it and before I go to any event), the alu a-arms should give you no trouble what-so-ever. They are just like anything else in that respect, including steel a-arms-----------ignore it and let it go bad, and it will bite you.

 

Oh, one more thing - ball-joint failure is more likely to occur on 944's that have been lowered - seems this puts additional stress on the A-arm.

-Z.

 

Get the rebuild kit from Rennbay. My car is lowered, and I put the geometry correction kit on the car. One of the guy's here had a failure, and screwed the front bodywork up on his 951. Didn't hit anything, just lost the driver's side suspension-

 

Hi Tifos,
Sorry if I sound negative. If I were to track my car I would
worry about those arms not just the ball joint alone. I mean
we are looking at a part which is 16-18 yrs old. Who knows
if it will break due to fatique. Anyway, going steel arms is cheap
insurance besides you get the benefit being able to change the ball
joint.

 

I'm pretty sure hazlgreen has aluminum control arms, he has an '85.5 944NA. For street applications the only really great things about the steel a arms is that they bend before they break, the aluminum arms just give all of a sudden but if you clean them up on a regular basis and inspect them you'll find stress fractures where it is likely to break. The ball joints themselves are replaceable in both steel a arms and the alum. ones just a matter of cost. I think the steel ball joints are like $30 each where as the aluminums are closer to $90 each and you have to make sure you catch it before it wears the pocket out.

J Chen, where are you in Taiwan? I'm heading over after christmas to visit family for about a month. I'll probably be all over the island while I'm there. Are there many 944's in taiwan? I don't remember ever seeing any over there when I was there 8 years ago. How hard is it to source parts there?

 

To be honest, I'm not sure if my arm is aluminum or steel. How different will the appearance be? I'm having a friend take another look at the arm in question tomorrow, I think.

I do not want to have a catastrophic accident - that is for sure. It certainly seems like the ball joint is loosening, but I want another set of eyes to look at it before starting an expensive repair.

 

The steel arms are black and the alloy ones are silver. The balljoints on the steel arms are bolted onto the arm. On the alloy arms, it goes in from underneath. The main problem with the lowered cars is that the angular movement of the ball-joint under full-compression can have the pin hit the side of the pocket that it sits in. Over time, this can break the pin or enlarge the hole and allow the ball-joint to pull out when the A-arm is relaxed down.