I owned GX 470 and RX 450H before, I thought they were very quiet SUV. After I test drive 15' Mercedes ML350, I found Lexus is really loud at high speed.

 

Every Lexus I've driven and ridden in excels at engine noise reduction and sucks at road noise isolation compared to similar Mercedes and BMW vehicles. Lexus feels quieter at low speeds, but the higher the speed, the louder Lexus gets compared to MB/BMW.

 

I think it has to do with Toyota/Lexus in general. They spent a lot in the 1990's and started cutting costs later on.

I was shocked when I bought my GS430 and found it louder than my mid 90's 2.2 litre 4 cylinder Camry. And the surprise: dash material, door lock latches and cruise control were identical!

Obviously that's an apples to oranges comparison in terms of tire size and performance, but it does tell you something. My Camry was whisper quiet up until you hit about 75-80 mph and even then it wasn't that bad.

That's not to say the GS is not a quality automobile. It has its strengths. After all I still drive mine every day

 

I think this has wíth the setup of the whole suspension to do and not only isolation in the cabin. Road noise is mainly transmitted thru the suspension and not the tyres as many may think. I am guessing that Lexus in general has cheaper/ less advanced suspension than many german competitiors. Even if you have the 19/20 inch wheels on a BMW or M package the road noise still stays low and even the comfort is pretty "good". Bumps and cracks in the road are not that bothersome.

Lexus cannot match that refinement and options like the F sport its only stiffer, louder and more harsh than the standard chassi on many models. That why I never bought the sport package on any of my 5 Lexuses I had.

I think its pretty clear that germans spend the money on the chassi and interior materials, while Lexus bothers more about reliability.

 

Germans definitely spend more money on the chassis, but the interior is definitely better in the Japanese vehicles. That is where the common man gets wowed right away when they step in the car.

 

This would make sense if it made a difference. I'm guesstimating but I probably put close to 150+ lbs of sound deadener in the RX. This was Kno knoise Kolussus, 2 per ft lead sheets enclosed in closed cell foam then finally 1 lbs per sq ft mass loaded vinyl. Over the wheel well I doubled up on the mass loaded vinyl. So total in all one could if they were good at math figure exactly how many pounds I put starting from the back passenger feet to the tailgate. I'm probably not to far off.

Did my gas milage suffer? Not one bit. I travel 90 miles each way to work and doing a steady 70mph I jus averaged 24 mpg. 17 gallons @410 miles. This with the occasional 75-80 passing then back down to 70 mph and maybe 10% city driving. I'm all for weight reduction but honestly the difference between what I had before & the silence I have now I would gladly give up a few mpgs. Happily I didn't have too.

 

That's true in some cases...but I don't think it can be made as a general statement. Many Japanese interiors are (and have been) second-rate in their trim, particularly with some older Nissans/Infinitis. The Honda Civlc, a few years ago, was severely panned for its El Cheapo hard plastic interior...so much so that they had to do an emergency update the very next year. Some 2008-and-newer Subarus also cheapened out their interiors.

Not only that, but German designed vehicles don't always spend more on their underpinnings. Some have also cheapened them out.........most notably from Opel and VW. Cheaper underpinnings, though, doesn't always mean worse performance........some still ride and handle surprisingly well, even with beam rear axles.

 

That sounds logical. I hear much less road noise in my S5 than I heard in my '13 GS F Sport. And I had changed my GS tires to Michelin Pilot Sports.

 

I've found a few of the Lexus I've driven or rode in over the years to be a lot louder in the cabin than I was expecting. It wasn't terrible by any means though.

My 2005 LS430 UL is pretty quiet and I drove an LS460, which was also quiet. My step-dad has an 09 GX470 and it's not as quiet as the LS' or even my SC300. It doesn't bother me too much when I drive it.

 

I think a lot of it is expectations. People drive the LS and they expect that every "Lexus" is going to be just as quiet, and thats just not going to be the case, and it isn't the case with any other manufacturer either. An $80,000+ LS is going to be a lot quieter than a $60,000 LX or GS, or a $40,000 ES or a $50,000 RX. If you compare those cars to cars they compete with you'll find that they compare more favorably.

I've said it many times, if you constantly compare other Lexus vehicles to the LS, they always feel cheap, but if you compare them to what they're supposed to be competing against the comparison shakes out differently.

 

^^^SW $40k, $50k, $60k, $70k or $80k EVERY car regardless of price SHOULD be like the $80k LS. What your saying is a cop out. Omitting $200 MAX of sound proofing in any class is poor judgement. Economies of scale and labor since it's stripped on the assembly line already may bring the cost of sound proofing down even more for such a large company as Lexus/Toyota. Beautiful interior, ride, blah, blah is fine but doing a half a donkey butts job and omitting noise reduction to save $200 and instead putting in 1/8" carpet over sheet metal is a job well done & call it a day? Here's an eye opener. Go into ANY entry level Toyota tercel and pull the carpet back & it's the same carpet over sheet metal philosophy.
"Passionate pursuit of perfection".

 

^^This! I've driven Camry, Tercel, 626 etc. To take off my back seat and stare at bare metal smacks of el cheapo economies of scale while telling the world that my GS is competing directly against a 540i.

I agree that a 80K LS is in a different league but how exactly would a car company expect its customers to aspire to that flagship if your entry and mid-level offerings make more noise than regular commuter car.

If the GS had been a Toyota Aristo, people might have forgiven the noise and parts bin issues. But to actually buy into the Lexus brand and paying a premium for everything and getting shortchanged on the basics.... well that's a bit of Toyota trickery.

 

It's a business my friend. Cars aren't built to what you feel they"should be", they're built to compete in certain segments. If they made every Lexus as quiet as the LS, what would be their selling proposition for the LS?

$200 in sound proofing per unit at a mass scale is a lot of money.

The GS is every bit as quiet or quieterthan a 5 series. I know, I owned one and cross shopped it extensively against the 5 series and everything else in its class. It's not as quiet as an LS, and neither is a 5 series. An RX is just as quiet as an Acura RDX or MDX, it's not as quiet as an LX. My ESs were as quiet or quieter than other entry level luxury cars at the time, not as quiet as the GS or LS. That's how it works.

 

Buick's Verano and Chrysler's new 200 prove that gas-powered vehicles don't have to be large or expensive to be cocoon-quiet. It's all a matter of how they are designed, and what the manufacturer is willing to commit to in sound-isolation.

 

I've driven both the Verano and the 200. They're quiet but hardly cocoon quiet. I find them similar to say a Camry.