What could cause this vibration?

[EvilCamaroSS]

The car could be turned off, key removed from the ignition, if you have a passenger stomp on the floor it vibrates throughout the entire car, even all the way into the drivers seat.

 

If you are parked near a road, and a tractor trailer passes by the side of the car, the entire car vibrates like a handheld back massager, where most other cars would just sway a little because of the air displacement.

 

What suspension part being bad could cause this? Or what if anything else could cause this?

[Scubaru03]

What does it do when you drive? Any noises? Is you exhaust secured and not flopping around?

[EvilCamaroSS]

What does it do when you drive? Any noises? Is you exhaust secured and not flopping around?

 

It vibrates when I drive, but let's leave that out of the equation because the dealer is telling me it's normal.

 

There isn't any banging, any movement in the car causes a vibration that reverberates throughout the vehicle. I'm just trying to figure out where to start looking.

[Scubaru03]

I would check bushings on control arms. But to kick the floor and get the noise leads me to the exhaust that runs under the floor board maybe loose.

[EvilCamaroSS]

I would check bushings on control arms. But to kick the floor and get the noise leads me to the exhaust that runs under the floor board maybe loose.

 

Thanks, I'm pretty sure the exhaust is in place, as it's been to the dealer 4 times for this issue thus far, and it seems like it would be pretty simple to see. Also there is no noise when you kick the floor board, just a vibration that goes throughout the whole car, you can even feel it in the seats.

[schnacko23]

The car could be turned off, key removed from the ignition, if you have a passenger stomp on the floor it vibrates throughout the entire car, even all the way into the drivers seat.

 

If you are parked near a road, and a tractor trailer passes by the side of the car, the entire car vibrates like a handheld back massager, where most other cars would just sway a little because of the air displacement.

 

What suspension part being bad could cause this? Or what if anything else could cause this?

 

Sound Bite to compare to our cars? Seems like a very odd problem, as one of the things I love about my car is the lack of cabin noise/vibration. (Save for the purposefully heard exhaust)

[Scubaru03]

Probably a bushing or mount of some sort maybe tranny/motor/body. Thats an odd i am curious to see what you find. Good luck.

[schnacko23]

You bought it used yes? Are you more then 100% sure the car was not in an accident? I dont want to assume it was, but it seems odd the shimmy wasn't caught by the previous owner and that this problem is so odd..

[EvilCamaroSS]

You bought it used yes? Are you more then 100% sure the car was not in an accident? I dont want to assume it was, but it seems odd the shimmy wasn't caught by the previous owner and that this problem is so odd..

 

I bought it used, certified from the dealer.

 

It was traded in, so I really don't know what the previous car history is, although it has no accidents on carfax, and I can't find any evidence that the car was ever in an accident.

[EvilCamaroSS]

I'm starting to think that this could be a tire/swaybar/whatever issue.

 

On the way home today with the car, the ride was feeling pretty fantastic. I had the windows down, sunroof open, and the only vibration I felt was from the audio system.

 

At a point in my trip, the road turns to single lane and I got behind a tractor trailer.

 

This is when the vibrations really started, it seems that the back draft caused by the trailers is tossing my car back and forth causing the vibration. If I put the windows up, it gets 10x worse. If I leave them down, the wind can now pass through the car instead of tossing it around, end result? Less vibration.

 

I backed off from the tractor trailer to get out of the draft and put my windows up, there was minimal vibration, definitely tolerable, when I put the windows back down, the vibration was gone all together.

 

Now, On to what could be causing this. It could be the tires, as the General Exclaim UHP's have a super soft sidewall, if you push down on the car you can physically see the sidewall bulging out with every bounce.

 

The second and more likely cause is the FSB.

 

What would everyone's opinion be on the tires? As that is a much easier thing for me to get Subaru to replace.

 

Also it's worth noting that the day the vibration was the worst was the day that it was really windy outside.

[schnacko23]

The buffeting of the wind is pretty normal, as I am sure you know, but for the buffeting to cause a vibration... It just seems like something in the suspension and or chassis of the car is not tight or working properly.

[iNVAR]

your passenger is sitting in your car and gives the floorboard a stiff stomp and you hear the noise?? that's something loose somewhere, part of the body or something. i highly doubt it has anything to do with sway bars or tires or anything else you're thinking about.

[EvilCamaroSS]

your passenger is sitting in your car and gives the floorboard a stiff stomp and you hear the noise?? that's something loose somewhere, part of the body or something. i highly doubt it has anything to do with sway bars or tires or anything else you're thinking about.

 

You can feel it, throughout the floor and into the drivers seat.