# Front Clunk After ZZP Lowering Spring Install?



## Thebigzeus (Dec 2, 2018)

Did this occur directly after install or did it take awhile to appear? Also, did you contact ZZP? They are pretty helpful and responsive to emails and might have an idea. I am currently tracing a clunk from drivers front, its not real loud, but happens over bumps only but not every time. I am stock suspension here except for Moog sway bar ends.


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## Gotta_Go_Fast (Apr 27, 2020)

Directly after install. And they are closed on the weekends, so I was going to call them tomorrow. If they have any advice I will happily share it here.


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## MP81 (Jul 20, 2015)

Sure sounds like what you're experiencing regarding the steering is bumpsteer, caused by the angle of the tie rods changing due to being lowered.

On the Cobalts, people sold steering rack spacers that moved it up in vehicle, which I installed after putting the lowering springs (among all the other **** - FE5 struts/shocks, FE5 front swaybar, FE5 lower control arms) in the vehicle. I actually found they caused major effort increases at low speeds and would cause the whole rack to groan. I ended up taking them out and the car really doesn't have an issue with bumpsteer - and it's been nine years, so I guess they weren't necessary.

In this instance...it sure sounds like they might be. Or something is loose. I presume you didn't need to touch the rack when doing any of that, right?


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## JLL (Sep 12, 2017)

Gotta_Go_Fast said:


> I recently installed ZZP lowering springs, sway bar links, and rear sway bar on my Sonic and it now has a horrible clunking noise. It clunks over almost everything and I'm having trouble narrowing down exactly what is causing this issue.
> 
> The Sonic top mounts are a bit different than the Cruze mounts. The top hat gets lined up with the tower, then you put a plate over the tower, then one nut is the only thing holding the plate on... It just kind of floats there. Its not actually screwed or adhered to the tower in any way. I have also noticed there is more slop in the steering if I'm turning and go over a bump. Specifically, when I turn into my driveway there is a fairly big bump and (I'm not exaggerating) it feels like the whole rack shifts and clunks louder than ever. Someone else did a post recently about their sway bar links causing a racket. Has anyone came up with a solution?


Did you get a good alignment afterwards? Lowering the car changes the alignment angles. Especially camber.

Also some lowering springs I have used in the past require cutting the bump stops. If I were to lower my car, I would replace the shocks and complete strut assemblies at the same time as lowering.


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## Gotta_Go_Fast (Apr 27, 2020)

MP81 said:


> Sure sounds like what you're experiencing regarding the steering is bumpsteer, caused by the angle of the tie rods changing due to being lowered.
> 
> On the Cobalts, people sold steering rack spacers that moved it up in vehicle, which I installed after putting the lowering springs (among all the other **** - FE5 struts/shocks, FE5 front swaybar, FE5 lower control arms) in the vehicle. I actually found they caused major effort increases at low speeds and would cause the whole rack to groan. I ended up taking them out and the car really doesn't have an issue with bumpsteer - and it's been nine years, so I guess they weren't necessary.
> 
> In this instance...it sure sounds like they might be. Or something is loose. I presume you didn't need to touch the rack when doing any of that, right?


I didn't touch the rack at all, but that is interesting. I'll have to look into that.


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## Gotta_Go_Fast (Apr 27, 2020)

JLL said:


> Did you get a good alignment afterwards? Lowering the car changes the alignment angles. Especially camber.
> 
> Also some lowering springs I have used in the past require cutting the bump stops. If I were to lower my car, I would replace the shocks and complete strut assemblies at the same time as lowering.


I have not gotten an alignment yet. I figured I should get the clunk issue sorted beforehand, in case I need to change out any suspension bits for any reason. I did cut off the bottom 1/3 of the bump stops in the front and the rear. The driver side strut was a nightmare since the bolts were all rusty and seized. Ended up having to dremel them off and get a new strut and hardware for it up top. Both sides clunk, so I imagine it isn't an old strut issue.


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## JLL (Sep 12, 2017)

Gotta_Go_Fast said:


> I have not gotten an alignment yet. I figured I should get the clunk issue sorted beforehand, in case I need to change out any suspension bits for any reason. I did cut off the bottom 1/3 of the bump stops in the front and the rear. The driver side strut was a nightmare since the bolts were all rusty and seized. Ended up having to dremel them off and get a new strut and hardware for it up top. Both sides clunk, so I imagine it isn't an old strut issue.


Why just replace 1 strut? That's asking for trouble in the future. It's kinda like wearing a new shoe and an old one. Before long your feet are gonna hurt.

Good luck finding your issue. I hope you find it before it creates bigger problems.


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## Gotta_Go_Fast (Apr 27, 2020)

JLL said:


> Why just replace 1 strut? That's asking for trouble in the future. It's kinda like wearing a new shoe and an old one. Before long your feet are gonna hurt.
> 
> Good luck finding your issue. I hope you find it before it creates bigger problems.


I only had enough money for one with Christmas coming up... Wasn't expecting this job to take so long and need to buy extra parts and stuff. I definitely want to get this resolved ASAP, as I like driving hard on twisty back roads. 

Thank you for the thoughts though


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## JLL (Sep 12, 2017)

Gotta_Go_Fast said:


> I only had enough money for one with Christmas coming up... Wasn't expecting this job to take so long and need to buy extra parts and stuff. I definitely want to get this resolved ASAP, as I like driving hard on twisty back roads.
> 
> Thank you for the thoughts though


I have learned from experience that when mod ding a car, its ALWAYS more expensive than the original part cost. Even more so as the car ages.


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## Gotta_Go_Fast (Apr 27, 2020)

JLL said:


> I have learned from experience that when mod ding a car, its ALWAYS more expensive than the original part cost. Even more so as the car ages.


That's a very good life lesson. I got plenty of that when I used to have a S13 240sx... Really miss that car though


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## Gotta_Go_Fast (Apr 27, 2020)

I FOUND OUT THE PROBLEM

Turns out the sway bar links had backed themselves off since install. Make sure you check them after you put a few miles on it! I might even consider loctiting them so this doesn't happen again.


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## JLL (Sep 12, 2017)

Gotta_Go_Fast said:


> I FOUND OUT THE PROBLEM
> 
> Turns out the sway bar links had backed themselves off since install. Make sure you check them after you put about a few miles on it! I might even consider loctiting them so this doesn't happen again.


That would definitely make a clunk. Glad you found the cause of the noise.


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## Thebigzeus (Dec 2, 2018)

Gotta_Go_Fast said:


> I FOUND OUT THE PROBLEM
> 
> Turns out the sway bar links had backed themselves off since install. Make sure you check them after you put a few miles on it! I might even consider loctiting them so this doesn't happen again.


The ones that attach to the strut?


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## Gotta_Go_Fast (Apr 27, 2020)

Thebigzeus said:


> The ones that attach to the strut?


Yeah it was the nuts on the sway bar link (stock its plastic). Both sides needed tightened, but the driver side was REALLY bad


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## MP81 (Jul 20, 2015)

That's weird! The Cobalt's (Moogs - because thicker) never backed off after I tightened them back when I put them on in 2010.

I should probably grease those...


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## -loki- (Dec 13, 2019)

Probably removed the link nuts to remove the strut to install the springs. Got so excited and maybe forgot to tighten them all the way. 😃


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