Can you show me the picture of that area have been removed ?
Thanks

Undercoating is a flexible material. I highly doubt it would transmit vibrations.

Here's my story and I feel like a fool. I bought an 2019 RX450H the last week of May 2019. After about 100 miles, the acceleration was rough and shaky. I dropped off the car for the sales and director to drive and was told it was "normal". Another 50 miles and it started to develop a drone at about 1.5K RPM and my ears ring after being in the car for 5 minutes. I was still reassured that it was normal. 10 days and 600 miles later, I took the car in for the Service manager to test drive. He told me it's louder and more shaky than usual, but it's "within operating parameters". Duh, whatever I told myself. I bought this car for my wife because she loves Lexus. So, here is where I went wrong. Instead of informing Lexus and have them drag it out, I settled with the dealer to trade for another car, but with a loss of $3.5K on the current car.

So, I test drove another 2019 RX450h, and it had the same problems. I drove another 2019 RX350 and it had the same problem. The RX450H loaner I drove didn't have the problem. I finally drove another RX350 extensively and it didn't have any issue. It's optioned out, so I ended up paying an extra $5K, plus the $3.5K depreciation from the RX450H, so $8.5K out of pocket.

Well, after 200 miles, the 2019 RX350 I purchased developed the drone and vibration issues. At 1500 RPM under cruising speed, the car vibrates and you can feel it in the pedal, steering wheel, and seats. It also has the drone, which is my bigger concern. I'm at a loss for word and feel like the biggest idiot. This is completely unacceptable. My previous Highlander and Tacoma are super smooth and even after 100K+ miles they are more smooth than the new RX350. How ridiculous! I'm going to have the TSB applied but I don't have high hopes.

Beware guys, the vibration and drone problems are not fixed at all, including 2019 models. My next trade up is going to be a Cayenne. Lexus has lost with me.

-4G

Well, don’t feel like a fool; learn from your mistake. You would have been much better stepping up to the V-8 SUV. I completely understand your frustration & that Lexus dealer screwed you over 9 ways to Sunday. Perhaps you have legal recourse, but that’s doubtful. The Cayenne is an awesome SUV. I looked at one, but they are considerably more money & VERY complicated machines. It will all depend on how good or bad your dealer is for your satisfaction with a Porsche. Good luck!

Trying to read all the posts, but admittedly it’s a lot. Are RX350 Fsports exhibiting the same symptoms, or it’s all models?

The RX 350 is the number 1 selling luxury suv in the states and this is the biggest problem some people have. Hell sign me up for another. I just came from an F350 diesel that took a crap and was denied warranty, cost me $18,600 for a new motor installed. I owed a bunch on the truck at the time so wasn’t worth scrapping. The kicker, the problem is well known in that fuel system and a very common problem. $60,000 truck that is only good for about 150,000 miles before you start having to replace parts.

ouch!!!!….

I've own many cars in the last 30 years. Most recently 2017 Highlander and 2006 Tacoma 4x4. They are both quiet and smooth. And they're $20K cheaper than my 2019 RX350. The RX vibrates at the cruising RPM range, so you get the vibration almost constantly, at times can be felt by the passengers. And the drone makes my ear rings and want to puke. These are not minor issues. If this is the new bar Lexus is setting, I never got the memo.

You’re right, the SuperDuty Diesels have many known issues, yet they sell a crap ton! I won’t touch a new diesel anything with a 10 ft pole - all are junk! My last one was bought back. I doubt I would buy the RX again. It’s had a lot of stupid little issues, but it’s just boring to drive. I look down & find I’m doing 85, so I have to be religious about using cruise control. I would like to test drive a V-8 LC & an RC. They seem like fun cars for the Lexus brand. If I need another SUV, I’m looking at the small V-8 model that’s nearly bulletproof.

The F Sport has no bearing on the problems. Most of the issues are on the RX 350. I have the RX 450h & it uses a CVT & doesn’t drone or vibrate the way the 350 does. I do have a heat shield rattle, but it’s minor.

So this drone and vibration you guys speak of happens when just cruising without pressing the gas? Even in sport mode?

all these issues the RX has makes me pretty sure they barely did any on road testing for the 4th gen. At least not in the same OCD way they tested the cars in the 90s in Japan where they were built back then.

The drone&vibration occurs between 1300RPM and 1800RPM for me. At exactly 1500 RPM with the foot on the gas, and no acceleration, the vibration is most pronounced. The vibration feels like holding an electrical hair clipper but on your feet. I feel it in the rear passenger seat when my wife drives the car. It varies with ambient temperature, too.

I just drove and tried to see if I heard a drone when feathering the gas and I couldn’t. But I have an f sport so it has that sound resonator so it always sounds slightly louder then the regular rx. Which RX do you have? What octane and brand gas are you using ?

There should be no difference in sound between a regular RX & an F Sport. The difference is in the trim - that’s it.

If you don't feel it, then congrats you have a good car! If you really want to test it, try to load up 3 passengers, go up a slight incline and keep a constant speed at 1500 RPM. If you don't feel it then you don't have the problems. I'm using Costco 92 octane.
I have altered my driving habit and not stay in that RPM range. I manually shift, now. It's ridiculous I have to resort to this. This kills the gas mileage, too. It's a good car, except for these problems. I'll probably get my wife something else and get rid of this one, or keep it and make it a project car and try aftermarket exhausts.