Any ideas on what would cause my front roll bar end link to fail like this? I recently replaced the shocks and springs (returned to stock ride height) and banana arms, and had it aligned by the dealer a few days before. I was going maybe 25 in traffic, turned to avoid a pothole and heard a bang, like someone hit something underneath with a hammer. This is what I found. I'm at a loss to understand why. When I changed the shocks/springs/banana arms, the links seemed fine. No play or anything. I torqued them to spec.

 

Never heard of a sway bar called a roll bar but I get what your laying down. Guess anti roll bar

Wouldn't give it too much thought, things get old and breakage happens... They are under lots of stress your sharp turn was just the stress it needed to give up on life.

 

Sway bar end link hardware is built of some pretty stout steel. When you installed it, was it up in the air? Did you check for any bind before you torqued it down?

Take a close look at the broken bolt itself when you pull it apart. The steel itself will tell the story: was it completely corroded abound the break, or was it twisted, yet clean?

 

Forgot you yanks call anti roll bars sway bars. Suppose it's because the land yachts you called cars back in the day would sway like hammocks in anything resembling a corner ...
Will check the broken link when I get a chance. Car goes to dealer in the morning to look at an unrelated issue (may actually be related come to think of it).
Yes, link was torqued with both front wheels in the air. One thing I noticed, now it's broken the rattle I had up front seems to be gone. Coincidence?

 

And therein lay the problem. Torquing any suspension bolts while at full droop causes erroneous torque and in the specific case of a sway bar endlink, there was NO WAY it could have been torqued to proper spec.

The rattle was not a coincidence, it was the sway bar end link rattling around due to improper torque.

 

Thanks, will do the replacements on the ground. I don't recall seeing this in the manual though.


Rattle was present well before I replaced everything else.

 

Easier is to either:

Do it on an drive up alignment rack. (Yeah, not that available... )

Or while it's on jack stands, use floor or bottle jack to raise up the LCA and torque when in the full "up" position. And if you can access it after the car is returned to the ground, check the torque again.

 

Come to think of it, I did check the torque on all bolts/nuts about 2 days later with the car on the ground. The link has a ball joint and the nut tightens on a shoulder on the joint shaft. The joint freely rotated while torquing - unless you have the Nissan special tool to lock the shaft you have to use a spanner (gear wrench) and Allen key to get it near, then finish with the torque wrench and hope it doesn't spin the shaft.


I know about torquing bushings while on the ground, e.g. bottom arms, as the bushings flex and if you torque at full droop it'll tear the bushing at full compression.

 

Sway bar end links are s metal joint. Does not really matter when torqued. They are free moving without a rubber joint.

3 possible causes.

The metal ball joint was worn and starting to bind. It did bind and broke.

You have adjustable front sway bars and are running them full stiff

Your car is slammed

 

Hmmmmm. I got schooled. Heh heh. OP, Len's right.... was just messing with my two other cars that have rubber bushed end links and using the ol' "torque 'em 'til they're just about mushed out" method.... Ooooops, my bad.

 

Suspect mostly the first one, coupled with a flaw or some form of damage. Photo shows what seems to be a flaw on one side leading to a stress fracture.


Car isn't slammed, and it's the original bar. Anyhow, had both replaced today, so back to drifting

 

It's all good, dude. Helps to talk about issues, and we all learn

 

Just torque them on ramps.

A seized balljoint could also have contributed to the failure. Either way the part is cheap enough.