034 Endlink Failure?

[bbeast]

I have had an 034 rear sway bar and 034 rear endlinks installed on my 08 RS4 for the past year or so. In this time, the M10 bolt that screws into the sleeve going through the swaybar has backed out of the right endlink on a number of occasions causing damage to the upper portion of the endlink. I have had it repaired by a professional shop and also repaired myself (each time using locktite to fasten the bolt when installing and the last time using fresh replacement components from 034), but each time with the same results. The bolt backs out and eventually unscrews completely leading to endlink failure and a very grumbly suspension. FYI, the sway bar is set to the stiffest setting and the endlinks are adjusted to their shortest position. Has anyone else had this issue?

I don't have any clue why this keeps happening - you would think the components would be compatible. I don't autocross or do any track days, so I'm not overstressing the suspension. I'm at my wits end now - any ideas on how to rectify the issue before I throw more money at it would be much appreciated. Thanks.

[ven0m]

I don't autocross or do any track days, so I'm not overstressing the suspension.

Welp, there's your problem.


On a serious note: question, do you tighten your end-links when the suspension is loaded or unloaded? To what height did you adjust the end-links? Do you have enough space to the CV axles? I'm running the same setup as you, with the same adjustment for 4 years now and no issues.

[bbeast]

Welp, there's your problem.


On a serious note: question, do you tighten your end-links when the suspension is loaded or unloaded? To what height did you adjust the end-links? Do you have enough space to the CV axles? I'm running the same setup as you, with the same adjustment for 4 years now and no issues.

I have thought of taking on the track, but I have another car for that, so the RS4 has always acted as more of my family hauler. I know this is no excuse though....

Anyway, I assume when the "pros" did it they had it on a lift and the suspension was unloaded, but I wasn't present for that. I know when I made the repair it definitely was unloaded. Should it have been the other way? I'll try to attach some pics to show what the setup is.

file5.jpgfile2.jpgfile4.jpgfile-4.jpgfile3.jpg

[RAudi Driver]

Sway bars won't line up with the suspending hanging. That being said your suspension was loaded when the bolts were tightened down. The front and rear sway bar take on a lot of force. Your bolts backing out is one drawback of stiffening up the suspension even more. Every time the bar loads and unloads, it's backing out the bolt a wee bit. Loctite will only work for a short period.

What I would do:

Make sure you start with brand new bolts. Old bolts stretch. I'm sure you have to as your old bolts probably fell off the car.

Introduce some lock washers into the mix.

Wire your bolts, like one would at the track on a motorcycle.

Use loctite again.

I reused sway bar bolt on my Cayenne and it backed out and fell off. It was a one time use stretch bolt so I purchased all new bolts and reinstalled. Lesson learned for me.

[ven0m]

I have thought of taking on the track, but I have another car for that, so the RS4 has always acted as more of my family hauler. I know this is no excuse though....

Anyway, I assume when the "pros" did it they had it on a lift and the suspension was unloaded, but I wasn't present for that. I know when I made the repair it definitely was unloaded. Should it have been the other way? I'll try to attach some pics to show what the setup is.

file5.jpgfile2.jpgfile4.jpgfile-4.jpgfile3.jpg

When you tightened your bolts and bushings for the sway bar in an unloaded position that was incorrect. The car needs to be sitting when you tighten ANY suspension component. Note: Given the end-links are aurora-bearings loaded/unloaded does not make any difference for them as they are able to rotate in their socket.

I think I identified your issue here: Looking at your first and third picture your axle is hitting your end link. Note the rusting ring on the axle where it shaved off the paint and a part of the metal. The length of the link is not adjusted correctly; make the link smaller by twisting the bearings on the thread-rod. On bumps your axles hit the end links and cased an additional shearing force on the bolt for which it is not meant to be under.

Additionally: Given the current wear on the holes in the sway-bar itself and the end link components where a solid connection is required it would be advised to either exchange the components or give them to a proper fabricator to refurbish the items to again fit-together.

[caliizaktiv]

Same thing happened with the scarring on my axle when the end link bolt head snapped off and I have the hotchkis bars. The suspension must be loaded to install or remove the front and/or rear bars.

[synaptik1]

I just had a 034 rear swaybar endlink bolt fail on my 2010 S5. Any suggestions on how to get the remaining piece of the bolt out of the control arm so I can install a replacement?