Ok, this is really hard to describe, but I am getting what I could only call kind of a "propeller" (like the prop in a plane) sound. Or like a fan, if you like. The sound roughly sounds like it is from the front, and is proportional to road speed, not engine speed. It isn't the tires.

Any thoughts?

 

does it happen in neutral?

 

Good question, I had to go for a test drive to verify it. Yes, it happens in neutral (if the vehicle is moving). Gear/throttle/RPM all seem to have no effect, only speed.

You would almost say a tire was rubbing against a piece of plastic, but I am very sure that is not the case.

It is a G35X in the event that makes a difference.

 

Warped rotor scraping across the brakes?

 

Hmm, that is an interesting idea; there is some (but not severe) rotor warp (noticeable on braking). If it was that, and I lightly engaged the brakes, I'd expect the sound to completely disappear, correct? I'll try that out.

 

I have had that noise happen when my wheel bearing needs to be replaced. Which unfortunately has been multiple times on both sides of my G35X

 

Wheel bearings is the one I worry about. It isn't that "grinding" sound my previous vehicles have had with bad wheel bearings, but hey, diff car, diff sounds. I'll go play with the brakes and try to exhaust other problems before I take it in to check the bearings...

 

try loading the sides by quickly swerving left to right and see the sound goes away or gets louder on one side.
i replaced my bearings last summer i think and it was more of a howling or wind tunnel sound.
i have that propeller sound right now too. i tried swerving side to side to see if the sound changes but it sounds the same. it could be something else. i have a g35x as well and my rotors feels like they are warped as they pulsate when i hit the brakes.

it could be the tires?

if you find where the noise is coming from i want to know too.

 

Wheel bearing time

 

Depends. Take it up to highway speed and lightly brake as if you were slowing down to get off at an exit. If they're warped bad enough, it would start sounding like a transport truck using its engine brake.

 

I had a similar sound and it was from a loose foam piece in the front of the car. It sits behind the bumper towards the bottom and seems to be for support or to direct air properly.

 

Ah, interesting test. Swerving left silences it, right makes it worse.

 

That definately sounds wheel bearing....have had very similar circumstances. And many wheel bearings, see my other posts.

 

Wheel bearing sounds most likely.

 

wheel bearing driver side.