I've got an RX of the same gen as yours and it does get noisy on less than perfect roads, even with new tires. I've replaced the door and window seals and that's reduced the wind noise a bit but the road noise is irritating.

My ES has much less wind noise but tire roar again is an issue. On smooth highways it's quiet but on worn out town roads, the rumbling annoys the heck out of me. Maybe applying some sound deadening materials to the wheel wells and under the carpet would help...

 

^^^ Yes do it. It'll certainly help.
Sound deadener+ccf foam+ mlv.
Just got back from Monterey and what should be awaiting me? Two wonderful packages with huge potential. Ready for the next phase. Just went halves on a mlv roll with a gent on another forum. Also ordered 2 lb lead sheet to see how malleable it is. Will. Kill. Noise. My goal is to get the interior down to 60 db or less @75 mph

 

Highway departments don't help much here, either, as the tendency, today, for safety reasons, is to repave roads with porous-type pavement surfaces that tend to prevent skids. Problem is, while enhancing traction, those porous surfaces also provide thousands of tiny little air-pockets between the tire surface and the road itself for tire and road-noise to creep into and get amplified.

 

Update.
Folks I just got through a 3 day marathon of an install while in between taking time with the family for breaks and what not. All said I EASILY spent 20+ hrs slapping, cutting, cursing, nip & tucking and pill popping advile this weekend. It was getting all the little crevasses customs cut that took the longest time.

So in overview this is what I did.
Sound deadeneer
2# lead encapsulated in PSA Ensolite foam.
1# Mass loaded vinyl.
Everything fit back together BARELY as in a playing card could not have fit in certain places and some I had to take off the lead & mlv because of fitment issues. The biggest benefit of all this was the HUGE increased in bass response and overall ease at which I can hear music again. Had to turn the bass **** down a bit.
Final tally was an 10-14 db reduction in sound while the average was 10.

I can tell you this. I'll NEVER do this again as it took to much time away from my family. Took a toll on my wife as I barely saw her but on the few occasions we went to lunch or errands. I value family and either I buy a quieter SUV next time or have someone do this. Besides, I'm no spring chicken and my fingertips, knees, back, shoulder and grumpiness is off the charts right now. This is a young mans game.

BTW, that second pic of the wheel well and where you can just make out the empty cavity would be a great place for a subwoofer. I measured it to be 6" deep by 7" length for the opening. Pretty substantial and could support almost any sub.

 

congrats, yeah i know it's a ton of work.

can't figure out where on the car that second pic is looking at.

 

Look's like the rear right strut tower, in the trunk area.

 

Yes. Right rear passenger side and half of the curve before it gets to the tailgate.

 

Yes it was. I have a greater appreciation for the installers who go through this. After all the improvements that I've achieved I still have to do the front of the cabin area. My order of ensolite failed to get here in the two days that I requested it. But perhaps that's a blessing as I'm in need of a serious break. The SUV smells like glue! Haha.

 

few years back, I did my MR2 and Prius, but in reality it is really hard to do because then some other noise becomes prevalent, that you didnt even hear before and now it might be even more annoying. In Prius, it was tire noise that became much "louder" when everything else dropped.

 

Now you will hear wind noises.

 

exactly right, it becomes noise whack a mole.

i did the whole back of my gs400, and did some of my miata when i had that.

 

Haha!. My wife riding in the back with our grand kid was evaluating the sound back there. I asked her how it was. She said all I hears is wind noise. When she turns her head to specifically "look" for sound she can hear the tires but other than that it gets her approval.

Next thread.
"How to combat wind noise using pulse laser vacuum atomic air splitter" or get 4" thick clear leaded glass.

 

Taking a douche move from the silly car "reviewers" that litter YouTube, let's just say its "sporty".
"why is my ride so rough?". Oh it's "sporty"
"why is my car so loud?". "sport" mode
"why does my steering wheel jiggle so much?" "sporty" feel
Im so sick of these reviewers, Consumer Reports included (here lately) downplaying luxury and calling it "sporty".
"why's my BMW spewing blue smoke out the tail pipe?". Oh it's the "sport" edition.
Lexus and Toyota need to IGNORE these airhead reviewers and stick to providing the smooth,luxury, isolated, cocoon of silence Toyota/Lexus built their reputation on.

 

Yaaaaaaaaaaaa!! It's worth it!!! Yes! First night of my commute back to work and on smooth asphalt all I hear the wind hitting the side view mirrors.

Hitting 70 db!! Down down from 82db!!!

Why I did this project. Below is the sorry excuse of carpet in the Lexus. Pathetic for an otherwise stellar SUV.

Next up!
https://www.clublexus.com/forums/rx-...or-carpet.html

 

I agree. I'd gladly give back 1 mpg if it meant adding ultra sound deadener to the ride. At least give us that option before it leaves the factory. I mean my goodness I can't believe the smoothness and NIGHT & DAY difference there is in the cabin and I have yet to tackle the front!
A little cheat preview. On a very smooth section of highway I did get to 69 db but flickered too much between 69-71 db to consider it a valid number. Anyway, never did I think I'd be hitting below 70's. But there it is.