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Looking for some help with some clunk'ing sounds after suspension change.

fumanchu182

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#1
So recently I changed out my sway bar end links with HHP Racing shortened end links. I also changed out the stock springs with HHP Racing springs. When driving slow or in a turn (body articulation) I hear a clunk under the car as if something is contacting the body. I have been underneath the car multiple times this week and have double, triple and quadruple checked all bolts to ensure they are tightened and still there. Things I have checked.
  1. Motor mounts: thought I might have broken my new solid ones.
  2. Exhaust: checked the entire length of the car, everything is fine (just had muffler and resonator deleted).
  3. End Links: Just installed the HHP Shortened end links (have 17" race stars), bolts are on and tightened to spec.
  4. Front/Rear Springs: Just installed the HHP Racing springs, everything looks fine.
  5. Drive Shaft: Have a DSS solid drive shaft, checked for any marks on it and none. I used a grease pen on initial install to make sure bolts didn't move and absolutely none of them have moved.
  6. Differential: Just a cursory outside look, honestly if it was this, any gear would let me know it was busted.
  7. Axles: Gave them the move by hand test, everything seems rock solid.
This only happens at slow speeds, in reverse or forward. Sometimes straight, sometimes in a turn and it is perplexing. I have done some logging and the engine/trans are 100% healthy. If this has happened to anyone else any advice would be appreciated. A friend of mine suggested a rear cradle lockout as he heard a similar clunk after moving to the 1320 springs.
 


Hpindy

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#2
Did you remove the lower rear shock bolts?

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fumanchu182

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Thread Starter #3
Did you remove the lower rear shock bolts?

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I did not do the spring installation as I didn't have the correct tools, I did take it to my usual installer (built his own Turbo Scat Pack and is lead tech at Bayside Annapolis Dodge) and he did the work. What would the effect be of removing the bolts in relation to the sound? I'll pass this information onto Mike so he can inspect it this evening. I'm dropping the car off at 6PM tonight.
 


Hpindy

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#4
I had to retorque the lower shock bolts a couple of times and with car on its tires . It drove me crazy till I figured it out .

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fumanchu182

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Thread Starter #5
I had to retorque the lower shock bolts a couple of times and with car on its tires . It drove me crazy till I figured it out .

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Good information, I'll pass it on. I know Mike uses UGGA DUGGA as a unit of measurement sometimes, I'll pass one the word to be a bit gentler this time.
 


moparjim

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#6
I had to retorque the lower shock bolts a couple of times and with car on its tires . It drove me crazy till I figured it out .

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I had the same thought.
 


moparjim

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#7
Good information, I'll pass it on. I know Mike uses UGGA DUGGA as a unit of measurement sometimes, I'll pass one the word to be a bit gentler this time.
I would start by putting the suspension under load and retorque everything.
I had the same shock issue as Hpindy at one point.
 


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fumanchu182

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Thread Starter #8
I had the same thought.
I would start by putting the suspension under load and retorque everything.
I had the same shock issue as Hpindy at one point.
But would it cause a clunk? I'm without my phone right now, when I go on lunch break I'll be able to upload a video of the sound.
 


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#9
But would it cause a clunk? I'm without my phone right now, when I go on lunch break I'll be able to upload a video of the sound.
Yes ! I have been down this road ........ Twice

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moparjim

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#10
But would it cause a clunk? I'm without my phone right now, when I go on lunch break I'll be able to upload a video of the sound.
What he ^^^ said.;)
 


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fumanchu182

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Thread Starter #11
Thank you wise sages, should this not be the solution to the problem I will report back. :)
 


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#12
I had the same thought.
Agree. For some really strange reason, they recommend the final torque with the wheels on the ground. See if that does it.

Did you change any of the control arms too? Remember some links (don’t know if yours will) make the sway bar bang the top of the AAD top arm.
 


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fumanchu182

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Thread Starter #13
Agree. For some really strange reason, they recommend the final torque with the wheels on the ground. See if that does it.

Did you change any of the control arms too? Remember some links (don’t know if yours will) make the sway bar bang the top of the AAD top arm.
no change of the control arms, still factory. Just printed out all the torque specs and found the part in the FSM where it all has to be torqued under load
 


DGatzby

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#14
no change of the control arms, still factory. Just printed out all the torque specs and found the part in the FSM where it all has to be torqued under load
Let’s hope that does it.
 


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fumanchu182

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Thread Starter #15
Played whack a torque for an hour...
955550B1-830B-4CF6-AE81-B0A729842EC3.jpeg 11EC063F-8F6C-4EF3-8C3E-64D3587617D7.jpeg 69CFBC04-829A-4FE0-B5C6-EE6894CC51C1.jpeg

Didnt fix it. Mike literally ran behind the car as I went left to right and we isolated it to the rear left. With that being said we re torqued everything and did the same procedure. Isolated sound to rear left shock. We are in surgery right now.

2D129413-87F8-40B4-A3F9-0A0C4D8FFC08.jpeg
 


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#16
Bad/busted shock?
 


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#17
When torquing did you check the top shock mount?
I usually try to undo the bottom only as I find it easier to recheck. But many undo the top as most instructions Say to do so.
Hopefully you find the culprit.
 


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fumanchu182

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Thread Starter #18
Bad/busted shock?
When torquing did you check the top shock mount?
I usually try to undo the bottom only as I find it easier to recheck. But many undo the top as most instructions Say to do so.
Hopefully you find the culprit.
We tightened the bolts in the fender well to spec. We also tightened the top bolt behind the carpet to specs again. Took it for a spin and still doing it. We also read the BCM module for the ADMS and everything reported as fine. All we can think it is at this point is a bad shock or potentially I need a cradle lockout kit. Im going to simmer on this and maybe mount a go pro in the fender well and just drive around the block.
 


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fumanchu182

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Thread Starter #19
It's back and now it's causing problems. Mike @ OST thinks that something is clinking, causing the knock sensor to artificially peg from the clunk so I'm open to suggestions, should I just start tearing it apart, get headers? Go back to stock springs as that was the only knob that was turned when they were installed. Thoughts?
 


moparjim

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#20
So something somewhere is likely hitting something somewhere.
Enough that the knock sensors are picking it up. Which doesn't need to be a big noise.

I remember a guy had a couple of fair sized clevices(and possibly some chain. I don't remember) on his hitch. Went to the dealer for lousy fuel mileage. The mechanic removed the clevices and the fuel mileage returned. The knock sensors were picking up the noise and pulling timing.

Ok story time over 🤣

Did you remove anything like say the exhaust. If it is over slightly it could be contacting something.
Look to see if the springs are seated properly. Is there supposed to be an isolator pad between the spring and mount?

Just a couple of things I have seen in the past.
 




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