Zbros 3" forward a arm WARNING!!!

[sledheadd]

I just want to let anyone who is running these a arms to check your lower ball joints. I had one break on me doing 70mph on a nice groomed trail, these a arms have less then 200 miles on them and have not taken any sort of impact at all.
It was scary to say the least.
It broke where the treads end, you can tell it had been working back and forth until it broke completly off.
I'll post a picture up later.

 

[JDen]

There is an update for the top ball joints. They are a little heavier now. I bent one of mine first ride on it right in the middle of the threads.

 

[sledheadd]

Mine was the lower ball joint that broke!!

 

[ruffryder]

what is with all the front a-arm issues for these sleds?

 

[judger101]

these aftermarket a-arms for the nytros are going to really get someone hurt or worse, but its ok they will have an another "update" for them....

 

[ruffryder]

these aftermarket a-arms for the nytros are going to really get someone hurt or worse, but its ok they will have an another "update" for them....

You don't see the heim joints being used very much on stock suspensions.. I wonder if this is why?

 

[Zipperno]

How did you manage to brake the lower ball joint? They arent heim joinst, more like automotive joints....

 

[bholmlate]

Hey Ruff

You see a lot of heim joints as well as ball joints being used in off-road racing and that is way more abusive then Sledding will ever be. You still see them break once in a while though. You might be right that the factory doesnt want to take that risk of one breaking though.

I think there is issues with the geometry in which these heims and ball joints are being used causing stress risers in them. Maybe in some cases people are over torquing the heim lock nuts onto the a-arms putting too much stress on the threads. I hate to bring it up but the weight over the front end of these sleds may also be playing a role with this as well.

It is really scary to think that you could loose for your front ends at 70 MPH unexpectantly I am glad to hear that the only thing that was hurt in this case was Sledheads pride as he flew over the bars no doubt.

 

[yamiman]

Ill be checking my lowers as both my top ball joints are bent, no impact at all. Ill be calling zbroz tomorrow, hopefully there is an update.

 

[yamiman]

Another note, when I installed this suspension I had a hell of a time to get it to 1 degree negative camber as I barely had any thread through the lock nut, I just used a crap load of red locktite. Are the arms made to run more negative?

 

[sledheadd]

How did you manage to brake the lower ball joint? They arent heim joinst, more like automotive joints....

Zipperno it broke a little bit higher up then your picture shows, right where the treads start from the bottom up.
You know I was sure surprised to see it broken I thought for sure the nut had backed off. I will be checking the other side for any signs of wear.

good thing it was early morning and the trail was still frozen solid I managed to ride it out, but my buddy behind me had to do some fancy stuff not to hit me.

 

[sledheadd]

Picture of breakage

 

[BBNytro]

Do you remember what you torqued the ball joint to?

 

[Zipperno]

Could the nut have backed out and then it rocked around in the spindle until it broke? Do you see any wear in the hole on spindle that could explain this?

Just thinking outside the box to find the cause....

 

[paulharris]

Was the nut overtightened? on this style of balljoint the taper takes all the load and the nut just needs to be snug to hold it in place. i don't see how it could break unless the nut was overtightend or the nut came loose. Was the nut a castle nut that takes a cotter pin?

 

[ruffryder]

Hey Ruff

You see a lot of heim joints as well as ball joints being used in off-road racing and that is way more abusive then Sledding will ever be. You still see them break once in a while though. You might be right that the factory doesnt want to take that risk of one breaking though.

I don't think they use them the same way though... It looks like they use them for single dimension forces. Either tension or compression, like a-arm mounts to chassis, ladder bars and other rear suspension parts.

The parts on these sleds are being applied to forces in two directions. One direction is holding the weight of the sled up, the other is keeping the spindle from being pushed backwards. The resulting force is larger than either of them. Neither of these forces is compression or tension on the tie rod.

I am starting to think this is part of the problem...

 

[bholmlate]

Hey Ruff

I think you may be correct in that line of thinking. I find it a bit odd that we are not hearing that people are bending these joints at all before complete failure. Maybe people are and just not reporting them until they fail. This leads one to believe that under certain circumstances the loads on the heim that you talk about in your post increases dramatically all of a sudden causing the part to completely fail rather then bend or deform.

It is a shame they are having this issue with these kits because it sounds like any one of these new front end kits make major improvements to the steering geometry of these sleds.

 

[BigFish BC]

Hey Ruff

I think you may be correct in that line of thinking. I find it a bit odd that we are not hearing that people are bending these joints at all before complete failure. Maybe people are and just not reporting them until they fail. This leads one to believe that under certain circumstances the loads on the heim that you talk about in your post increases dramatically all of a sudden causing the part to completely fail rather then bend or deform.

It is a shame they are having this issue with these kits because it sounds like any one of these new front end kits make major improvements to the steering geometry of these sleds.

if that was the issue then dont you think there would be more failing than there is,to me if that was the issue at least 50% of us would have had failed joints.

 

[bholmlate]

Hey BC

You make a good point. However, not everyone rides the same way and/or in the same conditions or has their sleds set up exatly the same way. there are a lot of variables to take into account here that is for sure.
That is why I said "under certain circumstances" because you would think if everything else being equal there would be a lot more people breaking their heim joints if in fact there was an inheirent flaw in the design. I am not saying there is a flaw.

I think we are gettting a little off topic here becasue this post was started becase sledheadd broke a ball joint not a heim a joint =) but he broke the bottom one which i believe is the same one the Skinz kit is having issues with so there are some parallels hear as well

 

[ruffryder]

any more problems with this front end?