jednav

Roll down your windows, drive and listen.

Just by chance hit the rear window switch while driving, and this
tunneling, deafening sound I heard coming from the rear.

Sound much louder from the driver side. RX also shakes.

I strongly suspect the tires (threads), but already booked an
appointment at dealership.

Problem could have been since day 1 and only concealed by
the sound proofing.

So roll down your windows and listen.

Grumpa72

This has been discussed before and is a normal sound, more or less. It is just a harmonic vibration set up by trapped air with no where to go. The only solution is to not drive with just the rear windows down. I have heard this in other cars to a much lesser degree but I believe the volume of the cargo section increases the problem.

Gary

mandyfig

I have experienced this also. I did not think it was related to a problem, Gary's right, it is the sonic vibration.

jednav

I have to disagree. Could be a different issue alltogether.
The sound I'm hearing is not normal by any standard.
I'm believe it is the tires with thread separating.

mandyfig

What kind of tires do you have on? Are you taking the car in?

tgdaman

First, you've got to give Lexus credit for the great soundproofing job, if you now only hear the noise with the rear window down.

You say the "RX shakes".........is this only with the window down or all the time? There's your answer to whether its harmonic vibration or something else. Have you tried driving with ALL the windows down, does this change the sound?

jednav

michelins. yes, appointment is on Tuesday. Will post findings.

jednav

With driver's rear window down, it is much louder. Sound is unbearable. It only shakes when rear windows down. Haven't tried with all windows down.

But what is the point? What is harmonic vibration? Where did this term come from? the dealer? or a layman trying to "normalize" the situation?

AlexusAnja

If it ONLY occurs with rear windows down, then how do you figure it's the rear tire? Come on, let's have some common sense here. If you only hear it when window is down, then it's ultrasound dynamics of air passing across your vehicles but there's an offbalance turbulance effect. It can happen with SUV, sedans, etc. Nothing really much you can do about, it's the dynamics of the vehicle. Don't drive with your rear window down...

My '99 has the same problem and it's not a 'defect' per say.

CK6Speed

iTrader: (1)

It is air turbulence like others are saying. It is normal in the sense it happens to many different SUV vehicles including the RX. Next time, duplicate the situation, only this time try opening your sunroof a bit. If the sound goes away you know what the problem is.

salimshah

Resonance has a whop whop sound. Some call it the helicopter noise. You can eliminate that by rolling down other windows. If the sound goes away, save the trip. If not, them it very well can be the rear tire.

Salim

CK6Speed

iTrader: (1)

The way I read it was that the entire RX shakes as well when he rolls down the rear window. I guess I could be misreading it though. We need to find out from the OP if the sound and shake only occur with the rear window down. The shake if it is the tire should continue and be noticeable even with the windows closed. If there is no shake of the RX with the windows up, that pretty much rules out the tires.

salimshah

Half of the diagnosis [to pick the right possibility to check] is based on how the symptoms are described.

Physiologically, the human ear drums, determine motion [you marvel at the nature how far the sensors are from base (feet) to determine motion and how close to brain it is to take corrective actions]. ... back to the problem

Not that I disbelieve the original post, but would like to eliminate a possible co-relation. The motion should also be sensed with or without the window rolled down.


Salim

mandyfig

This is definitely an interesting case. Keep us posted.

Tony

All cars regardless with sedans or SUVs experience this wind buffeting effect. Cars are getting so air tight that when you let in air with no escape it tries to go back out and bounces around causing that vibration. Just crack your sunroof and or the front windows and you will be fine.