Front end clunk
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#1: Front end clunk Author: dozier77Location: Tempe, AZ PostPosted: Mon Oct 10, 2016 1:49 pm
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Yeah, a ton of threads about this on the interwebs with lots of different possibilities, but my situation is a little specific, so I wanted to see if anyone had any ideas.

I've been running the OME medium suspension for over four years. Just recently I realized the spring cups had been installed upside down (they were facing downwards like the stock cups, instead of upwards like the OMEs are supposed to). So, I took it apart and changed them. I also replaced both tie rod ends. Ever since putting it back together I get a substantial clunk when the suspension rapidly goes to full droop. This did NOT happen prior to the work I did. I have the stock UCAs, but I've verified the issue is not them hitting the spring. I've also tightened the top nut on the tower as well as I can. When jacking the front end up via the middle of the skid plate (simulating full droop) nothing seems to be hitting, and the clunk doesn't happen. I'm unsure if this actually creates full droop or not. I believe I clocked the spring cups correctly when reinstalling, and I don't see anyway the cups are making contact during the droop, so I don't think that's the issue. Driver side is definitely doing it, but I'm not sure about the passenger side.

I have a couple of quick videos of the issue in action:





Any suggestions?

#2: Re: Front end clunk Author: Homedad PostPosted: Mon Oct 10, 2016 2:17 pm
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Sway bar hitting spring....look for scrape marks on inner spring one or two coils up.

#3: Re: Front end clunk Author: Homedad PostPosted: Mon Oct 10, 2016 2:24 pm
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I stand corrected.....second vid...full droop...sway bar hitting steering arm...obvious mark on top of arm.

#4: Re: Front end clunk Author: dozier77Location: Tempe, AZ PostPosted: Mon Oct 10, 2016 2:43 pm
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Hmm. I'm not seeing it, or maybe I just don't know what you mean. I don't see the sway bar coming anywhere close to any other component. Which part is the steering arm? Is that not the tie rod?

#5: Re: Front end clunk Author: Homedad PostPosted: Mon Oct 10, 2016 3:03 pm
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yes..the inner boot ring looks to have a mark on top

#6: Re: Front end clunk Author: gliderazLocation: avondale PostPosted: Mon Oct 10, 2016 4:30 pm
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Looks like homeboy is right.
Looks like sway bar is tapping the tie rod.

#7: Re: Front end clunk Author: FatRat PostPosted: Mon Oct 10, 2016 10:58 pm
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Yup, I have to agree with Homedad and glider. Tapping the top of the tie rod

#8: Re: Front end clunk Author: JimbolioLocation: Tucson PostPosted: Tue Oct 11, 2016 7:14 am
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Take the anti sway bar off and see if this addresses the clunk
Great documentation by the way


Last edited by Jimbolio on Tue Oct 11, 2016 10:16 am; edited 1 time in total

#9: Re: Front end clunk Author: calichaos PostPosted: Tue Oct 11, 2016 8:13 am
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+1 for the great work on the documentation..

I'd say do a SAS and that clunk should just go away. Smile

#10: Re: Front end clunk Author: dozier77Location: Tempe, AZ PostPosted: Wed Oct 12, 2016 10:46 am
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Front skid and sway bar removed. Clunk remains.

#11: Re: Front end clunk Author: 4GaugeSurpriseLocation: South Mtn-ish. PostPosted: Wed Oct 12, 2016 11:12 am
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dozier77 wrote:
Front skid and sway bar removed. Clunk remains.
Look very closely a the area around each bolt / nut for a clean halo. This is how I found a few clunks, specifically my lower shock mount.

#12: Re: Front end clunk Author: TOY4WDLocation: Mesa PostPosted: Thu Oct 13, 2016 10:09 am
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Is it possible that you are over extending your shocks now? I assume flipping the cups over yeilded you some more lift than before. Therefore extending the shocks that much more than before.

#13: Re: Front end clunk Author: dozier77Location: Tempe, AZ PostPosted: Thu Oct 13, 2016 2:15 pm
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I do expect the shocks are getting more extension now because of the change in the cups, however, this is the way it was meant to be. It's an OME kit. How could they be getting overextended? Something else in the geometry would have to be wrong, right? Worn out ball joint on UCA? Hell, a lot of people run aftermarket UCAs with these kits which should allow for even more travel..

How do I identify if it is indeed the shocks overextending?

4G, I'll be taking a closer look this weekend.

Any more suggestions?

#14: Re: Front end clunk Author: dozier77Location: Tempe, AZ PostPosted: Mon Oct 17, 2016 1:20 pm
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Looked at this over the weekend with another non-member and we couldn't figure out what it was. Leaning towards something with the shock itself, whether it's going bad, or whatever, so I think I may just replace it and see if that corrects it.

#15: Re: Front end clunk Author: BellyDoc PostPosted: Mon Oct 17, 2016 4:01 pm
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Shocks have an internal top out stop. This is what stops the shaft from flying out the end of the tube when compression is released. Shocks built to be coil-over struts have to incorporate a reasonably beefy top out stop because it's not just the internal nitrogen pressure pushing on it, it's also the spring preload. Depending on the valving in a shock, it may offer very little resistance to travel in the extension direction, so that the wheel can quickly be pushed by the spring down into the low spot after a bump, so you don't lose steering in washboard conditions.

The reason I mention this, is that if you're noticing the clunk in the instant that the suspension goes into full droop, it could just be the internal top out stop getting hit.

It could be that when you flipped the cup over, all you really did was increase the preload slightly, making the already somewhat beaten top out stop take a slightly harder hit at full droop.

For rebuildable shocks, there's typically an elastomer donut that goes on the underside of the end cap with the shaft seals in it.



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