Question about coil over noise on street

[ahtoxa11]

Hey guys, my OCD is making me think there is an issue, but I suspect there’s not. I’d like to hear what you think and learn what causes this noise.

I have kings on my 4Runner and noticed that when I hit a sharp edge on load like a large crack, recessed manhole, etc, I get a hollow-ish noise. Sort of like a thunk but less pronounced. I think it comes from both front and back but the rear is more audible.

Is this due to spherical bushings transmitting more NVH? It’s kind of inconsistent and sometimes I hear it on chattery surfaces such hardback snow.

Cannot hear at speeds above 40 or so. Cannot hear on bigger hits. Ive been out wheeling a few times since I noticed this noise and when I’m going down trails everything is completely silent on the outside - I tested this today in the mountains on a snow packed trail with fist size rocks and larger. No noise outside and mostly quiet inside.


So the noise is only heard inside and really mainly on the road. Also, maybe a coincidence but it’s louder when shocks are colder? I go down a trail for a few minutes and it seems to quiet down. Maybe it’s in my head.


Sorry for long post. Just curious to know what this is.

 

[honda250xtitan]

my vote is NVH. Race truck parts make race truck noises. i'd recommend not doing heim/uniball uppers lol

 

[ahtoxa11]

my vote is NVH. Race truck parts make race truck noises. i'd recommend not doing heim/uniball uppers lol

Yeah, my ocd comes and goes and once I fixate on a noise it’s hard to move on. I’m ok with race parts making race noises so long as I understand what causes them. Then my brain is accepting of that. Strange stuff.

 

[comtn4x4]

Yeah, my ocd comes and goes and once I fixate on a noise it’s hard to move on. I’m ok with race parts making race noises so long as I understand what causes them. Then my brain is accepting of that. Strange stuff.

I'd say it's the spherical bearings as well. In my experience a higher load rated tire will exasperate it as well.

 

[ahtoxa11]

I'd say it's the spherical bearings as well. In my experience a higher load rated tire will exasperate it as well.

Yep. Since it seems to be happening both front and back as well as both sides (hitting manhole covers) it’s not very likely an issue on multiple vehicle corners.

I run BFG AT KOs in load C. I’ve also noticed this more when it’s colder, so possibly colder tires mean slightly stiffer and more noise is being transmitted? Sounds logical to me.

There was a post by a gent here that had the same issue on his rear driver side with multiple shocks that used a spherical bearing. He solved it with a specific washer. I reached out to him for specifics.

 

[comtn4x4]

Yep. Since it seems to be happening both front and back as well as both sides (hitting manhole covers) it’s not very likely an issue on multiple vehicle corners.

I run BFG AT KOs in load C. I’ve also noticed this more when it’s colder, so possibly colder tires mean slightly stiffer and more noise is being transmitted? Sounds logical to me.

There was a post by a gent here that had the same issue on his rear driver side with multiple shocks that used a spherical bearing. He solved it with a specific washer. I reached out to him for specifics.

I tend to notice it much more in the front but that's me. I definitely notice my E rated tires stiffness much more in the cold until they warm up. Seems like the stiffer tire translates more of the road "feel". Increased tire pressure does this too.

 

[ahtoxa11]

Thanks for the responses so far. I must not have noticed the sounds until it got colder or maybe I just started listening to it more.

 

[rhadam]

After installing my Dobinson's lift there are clanks and bangs and weird sounds depending on driving terrain. I was always worried something was wrong until I spoke to enough people that said if it's installed correctly, those noises just come with modifying the suspension.

 

[ahtoxa11]

Well, uh, I hate to admit this, bit I think I found what was causing most of the noise I was hearing.

It was a small roll of tape that was placed on the flat plastic part of the hatch floor near the rear-most cargo tiedown. It bounced a little on sharp bumps making the hollow thunk-y noise. It blends with the plastic so well that I didn't even notice it there. Went back there today to triple-check things like the bottle jack and tire change tools and what do you know? When I jostle it around it makes a noise that I was hearing.

Drove it around for 20-30 mins after this and haven't heard anything unusual. The rest of the noises are what I'd consider normal given hard mounts.

:suspicious::suspicious:

 

[Mudballz]

I have the OME bp51 suspension and I get the same hollow sounds that disappears as I drive I think it has something to do with the oil temp of the shocks the same has been said about the pro suspension as well both the bilstein and fox setups
:hunter:Mike

 

[rhadam]

Well, uh, I hate to admit this, bit I think I found what was causing most of the noise I was hearing.

It was a small roll of tape that was placed on the flat plastic part of the hatch floor near the rear-most cargo tiedown. It bounced a little on sharp bumps making the hollow thunk-y noise. It blends with the plastic so well that I didn't even notice it there. Went back there today to triple-check things like the bottle jack and tire change tools and what do you know? When I jostle it around it makes a noise that I was hearing.

Drove it around for 20-30 mins after this and haven't heard anything unusual. The rest of the noises are what I'd consider normal given hard mounts.

:suspicious::suspicious:

Classic. At least you found it. I've been there.. tearing my hair out trying to diagnose a noise when it's something simple and probably right in front of your face. Had that happen with spare tire chain. Rattle was driving me insane until I saw on forums someone speak about that being the cause. Yup, it was.