dinnerzone

Hey fellas, I've been searching on and off for weeks and I'm having a difficult time getting to the bottom of this issue. Recently had my air struts replaced with KYB GR2 struts and RsR down springs, installed by Toyotechs for those of you in the Atlanta area who may be familiar.

Ever since the replacement, I've noticed a small pop/creak when going over certain bumps and speedbumps. I took it back to them to look over and they were not able to find anything, staying the struts were all in good shape and to spec.

It's starting to drive me crazy, and I think the pops are starting to happen more often.

From what I've been able to gather I should probably look at either the sway bar end links, or the sway bar bushings.

Is there anything else I need to be looking out for, assuming the struts are properly installed? The fronts don't make any sort of noose like this.

Any information would be greatly appreciated. If this is just something like coil slap I'll have to live with it until I can do something about it, but if Im doing damage to my car is like to address it ASAP

Aus430

Which strut mounts did you use? Toyota or KYB or one of the others?

dinnerzone

I bought the KYB rear strut mounts, but realized they didn't come with any kind of rubber insulator/boot like the fronts do, and don't seem to exist in aftermarket form, so I sourced the Toyota OEM for that bit.

911LE

I would guess it's the sway bar end links. You can drive with them disconnected over a known noise-causing bump to see if it fixes the problem.

Aus430

Am I correct in understanding that the Toyoya part is the one currently installed?
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dinnerzone

Yes, part number 48257-22070 Rear insulator, using the KYB rear mount SM5566. The struts, mounts, front insulators and bump stops are KYB with the exception of the rear bump stops. I could only find saachs 900096.

pmesfun

I'm guessing the noise wasn't present with original air struts? Can you have someone else drive the car and you ride in the back? Then if you hear the noise near the headrests that is the strut mounts.

Aus430

So KYB mount, toyota insulator kyb shock.

In the swap from air struts setup is there the thin metal 3 hole spacer at top that the 3 mounting nuts tighten down onto (between the nuts and body) ?

And I take it all the nuts were torqued in place correctly including the one for the strut itself?

LeX2K

KYB mounts are hit and miss.

dinnerzone

This part I'm not terribly sure about, as I wasn't present for the swap itself, I had to drop it off. But since you've mentioned it. I'm curious if that little shim/gasket is present. I would imagine if it's supposed to be there it still would be. The guys I've been working with are very by the books, and only use OEM unless someone like me hands them a car with 4 struts in the back seat, but air conversions are not foreign to them. They're known to swap out the bags from the GX series pretty frequently.

After more homework, and trying to listen out for the noise, I've narrowed the possibilities down to three

1. New Sway bar linkages. And/or sway bar bushings
2. Coil slap. (I did not think to get those coil silencers installed before doing this.

3. Potentially bad strut mount/insulator in the rear. It is a Toyota OEM insulator under a kyb mount so I suppose it's possible.

but based on when the pop noise happens (going over humps/bumps diagonally, slowly over speed bumps, basically whenever near full compression happens, but not sharp small bumps), I'm leaning towards the sway bar linkages. At least I really hope that's the case.
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dinnerzone

This part I'm not terribly sure about, as I wasn't present for the swap itself, I had to drop it off. But since you've mentioned it. I'm curious if that little shim/gasket is present. I would imagine if it's supposed to be there it still would be. The guys I've been working with are very by the books, and only use OEM unless someone like me hands them a car with 4 struts in the back seat, but air conversions are not foreign to them. They're known to swap out the bags from the GX series pretty frequently.

After more homework, and trying to listen out for the noise, I've narrowed the possibilities down to three

1. New Sway bar linkages. And/or sway bar bushings
2. Coil slap. (I did not think to get those coil silencers installed before doing this.

3. Potentially bad strut mount/insulator in the rear. It is a Toyota OEM insulator under a kyb mount so I suppose it's possible.

but based on when the pop noise happens (going over humps/bumps diagonally, slowly over speed bumps, basically whenever near full compression happens, but not sharp small bumps), I'm leaning towards the sway bar linkages. At least I really hope that's the case.
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911LE

Could also be a ball joint damaged during the strut install.

Aus430

The sway links are easy and cheap to replace though It's highly coincidental for them to go at the same time as a strut swap. Especially as you can install the struts without touching them.

My feeling is that it is the kyb strut mounts. There are a few posts here that I've seen over the years commenting to use OE mounts where possible. I recall one post had photos comparing the kyb and oe mounts but can't seem to turn it up to link to.

dinnerzone

It's entirely possible that it's the mounts, though it's funny that it's both rears making a fuss while the front mounts are quiet as a mouse. I thought it may have been the interaction between a KYB mount and the OEM insulator/boot, though it appeared to be designed with the OEM insulator in mind? Like I may have said previously, I was easily able to find aftermarket front insulators, in fact the KYB front mounts include it, but no such thing exists for the rears curiously. At least, as far as I was able to search.

I do recall hearing SOME noise in the rear before the replacement, most notably when backing out of my garage and rolling off the little 3cm slope leading to the driveway. Same kind of knock/tap, though I wasn't able to hear it as clearly due to the sound the air struts would make over it. In my memory the two sounds seemed like one thing. The kind of knocky/warbly sound you get when the bags are good but the juice has leaked from the struts, shocky and bouncy.

I gave it a very brief peek on my lunch break and grabbed ahold of the bushing some. it did feel a little deteriorated, but I couldn't get a good look. The links look like they may have been replaced at least once before. I did have to replace the front lower ball joints and bushings when I initially purchased the car, so I wouldn't be entirely surprised if anything with a bushing down there is nearing the end of their service.

I've been trying to pay attention more to the specific kinds of bumps and shifts that cause the noise and it seems like it's more about travel than shock. Smaller "shockier" bumps are quick and responds normally. But going slowly over moderately sized speed bumps and I'll get the mild creak or pop depending on how quickly the rear wheels go over it, and seemingly how far the rear dips.

The times I hear the little pop the most is leaving a driveway or going over a bump at an angle, say one wheel contact before another. In my mind I can see the sway bar doing it's work in this time, and can't help but think that may be it. Though like you said, I've heard some talk about the KYB mounts as I was researching and sourcing parts.

I really appreciate the troubleshooting and advice. Relatively soon I plan to get it up on a jack and see if I can find any play or see if I can't find some obviously worn bits, though it's all cheap and easily accessible enough that I may go ahead and replace the links and bushings regardless.

pmesfun

Keep us updated on what you find.