Did you get a chance to drive it or were you just going by that review? The guy in the review (imho seems even nuttier than most guys doing these reviews) says something like "it's noisier than what I expected"; what does that mean? I looked at a couple of other reviews like this one from these other two nutty guys who use actual sound testing equipment and at 7:40 they test it at just under 52db which is on par with the X7 (they indicate that they test all the cars on the same road...) and X5, two of the supposedly quietest cars on the road today:


Also... the 550h+ comes with 22" wheels, which will bring in much more road noise into the cabin vs the 20" on other TX (and RX) models. Also depends on which tires they're using...

As to the wind noise, there were some posts on this forum regarding whether the 550h+ has acoustic glass or not (and what type / level of acoustic glass it is, apparently there are many levels...) but it's still not clear to me... anyone drive a 550h+ and can share some first-hand impressions regarding the road / wind noise?

 

I would agree that it’s not especially quiet inside, it’s not loud but it’s very mainstream, similar to like a Telluride etc. An X7 is a much quieter vehicle.

Also most cars are quiet at the speeds that those Car Confections guys measure sound pressure. Take readings at 75 on a busy highway and you really see differences. At 50 MPH on a quiet road I bet my S560 and my Pacifica are similar in sound pressure readings. 75 on the highway the Pacifica is 4 db louder, which is a considerable difference. The TX I drove measured 63 db on that stretch of road, same as my Pacifica (S560 reads 59). Palisade/Telluride 62-63, very similar. X7 I drove read 60

 

The other thing to consider is subjective tone not just DB/sound pressure. Low tones will be less noticed and annoying than high pitched ones like wind noise that cause only small pressure changes.

Not really the same thing but in the firearms world certain suppressors will sound far far more quiet than others even if the measured DB is slightly higher. Great example is the B&T Station 6, it comes with a wipe can that is perceived to be insanely quiet.....however on a meter it's somehow "worse" than a full length silencerco can. 3 DB "worse" but irl the wipe can is not audible from one room over and the full length can is audible from over a whole floor over.

But if you went by DB and not what is actually heard you would write off the wipe can.....



Same thing happens with cars. That's why an LS460 is quiet as hell on a meter but subjectively doesn't "feel" as quiet an a S class due to tire noise being more noticeable to the ear than the meter vs wind noise. They are both similar according to a meter but have vastly different feels, and this applies to ALL cars since they intend for a certain "feel" to a given product. The TX feels like a Toyota.

 

I havent driven it past 50 during a test drive but it was on local streets with cars and rough pavement. It was a base model and to me it was very quiet, even the much hated 2.4t was really smooth and quiet. Surprising lack of road noise but it was also on smaller wheels and tires. I did feel minor shudders going over speed bumps and broken pavement and I think that is to be expected from such a large unibody vehicle and at this price point.

 

Really all modern cars are very quiet in those situations, you need to drive it at highway speeds to really see the differences in noise levels. 2.4T is fine until you really get on it, then it sounds like a 4 cyl...for most people that is a better engine than the old V6, has better torque down low.

The TX is quiet, but its "normal" quiet, its not a car that you're going to ride along in at 80 and say "Wow this thing is so quiet". Nothing else in the segment is that way either, have to go to X7/GLS etc etc to get that.



Thats right, all Lexus vehicles struggle with isolation from road noise, thats why tires are so important for them.

 

I wouldnt say all Lexus vehicles struggle with road noise. I dont have that issue with my GX and trust me, I would NOT have bought it if had horrible road noise since I'm extremely sensitive to that and rattles inside the cabin. Also, my GX have terrible Bridgestones with light offroady treads that would create road noise. Wind noise is noticeable above 70 but I quite like the white noise it creates and I find it relaxing, but I'm also a weirdo.

 

Your GX is body on frame, thats different. I will amend that to say all unibody Lexus vehicles. BOF vehicles benefit from a whole frame between the cabin and the wheels.

 

My GS 350 is nice and quiet on smooth roads. But on coarse roads the tire roar comes thru. The engine, however, is almost completely silent……

On my RX 350 the tire noise, engine noise, and wind noise all sort of blended together and I didn’t really notice the tire noise much.

 

Yea I had 2015 GS350 and road noise became a problem on regular highways above 50mph. Strange that Lexus touts they lined the floor pan with sound deadening asphalt.

 

It doesnt seem to be consistent. I had a 2008 ES that came from the factory like someone in Canada forgot all sound deadening. Then I bought a used 2019 and it was tomb like, but it was also build in Japan. So hit or miss and more miss than hits I suppose.

 

You guys need to compare apple to apple. You can't really expect GS to ride like GX. Part of the reason why GX is more quiet is because of high side wall tires. The only one SUV that I think is similar and more than GX is GLE/S. X5/7 need to have more rubber to be quiet. 21+" is as "quiet" as a GS. This TX's ride is fine IMO.

 

Different generations and likely on different tires. Tires make a huge difference.

Biggest reason why the GX is more quiet is the BOF construction.

Every review I have read says the X5/7 is quieter than the GLE/S BTW. They’re pretty similar.

 

Framed vehicles have a crazy isolation advantage for road shock and noise due to an additional set of body mounts and shock dispersion effects of the frame. Drawback is stiffness and directness along with the obvious hight/weight, they are amazing to have for trucks etc due to easy modification and general durability.

When comparing cars you need to have at least the same tires, I had/have the exact same tires on my LS430/460 and both A8s and since I have preference for UUHP tires they are inherently loud. Road noise is not Lexus's strong suit, a lot of tones make it though and we are talking about LSs not GS/ESs that are easily louder even to laypersons. My loaner ES250s on comfort GT tires are ALWAYS louder to ear and meter than even the LS430 was.

Tires make the car/really define the driving experience so I want my nice cars to be quiet with the tire I like to drive on. It's fairly easy these days to get a quiet car, but a quiet car that is also sharp and can more than double suggested turn speeds and beat factory braking figures etc while still maintaining ride comfort and being reasonably light is quite difficult.

Lexus just takes the path of quiet by being soft. It took at little bit to firm up both the LS430 and LS460 to be acceptable. Former needed a euro suspension conversion and larger rear sway bar and the latter needed a larger rear sway and front subframe adjustment for more caster. That way they are actually pleasant to drive

 

Would the subframes on some unibody cars serve this same purpose in terms of isolation?

 

I doubt it, they don't typically have the same mounts and isolation from the unibody the way a BOF vehicle has from the frame.

Its also physical distance. A truck/BOF vehicle you are just further off the ground...