arigold520

Hi all! New owner of a 2016 RX350 and my first Lexus! I started noticing that there is a rumbling sound from the exhaust/engine/somewhere (can't pin point where) as I accelerate. Since I have never drove other RXs, not sure if this is normal or not. It does not sound like it's an issue that needs to be repaired.

Thanks in advance!

websurfer

Is this a CPO Lexus?

arigold520

It is not a CPO, however purchased from the dealership. There is no warranty.

dibl

That is the so-called drone that you find in multiple posts on the forum. It's a feature. They raised the horsepower of the 350 engine by 45, from Gen 3, then, for fuel economy, programmed the transmission to use higher gears at slower speed, thus lugging the engine. It makes the exhaust system resonate. You can prove it to yourself by manually shifting it, and using higher shift points than the automatic transmission does.

vmoldovan

I can also confirm that my 2017 RX 450h executive (Canada) has drone issue as well, at 1700 rpm approximately.
There is no tsb for this.
Lexus dealer opened a support case with Lexus Canada in April but that where this issue is. Dealer didn’t change any other things related to this but fixed the following:

I had heat shield chirping over rear muffler, dealer fixed. If you have any chirping/clicking noise in cabin, check here (RX450h)) - ClubLexus - Lexus Forum Discussion

I had rear suspension support /control arms changed under tsb due to rubber squeaks on bumps (L-SB-0030-19)

I had master break cylinder changed under tsb due to squawking noises when pedal depressed (L-SB-0004-19).

Regarding drone. I bought weight mentioned in this thread and tried mounting before catalytic converter, right at the flex join, and right before muffler in the back, 2 places This didn’t help, and I want to try other places. It is just no fun to crawl under SUV to remount it

when SUV just gets started, I often don’t hear it, but it comes later, sometimes more pronounced than other times. 1700 rpm is about 110 km/h, quite common speed for me so it bothers me on highways. It does need to be either constant 1700 RMP under slight load or accelerating and keeping engine RPM at 1700, then it happens.

otherwise, planetary transmission is butter smooth, no vibrations. Every time I drive loaner, I get reminded that 450 is smoother vehicle.
Therefore, I like SUV in general, except drone noise of course.
In general, RX has unnecessarily boomy exhaust. On my old 2004 sienna exhaust is whisper quiet in comparison

I have not given up in trying to find a way to eliminate it. When I do I will update this thread.
Thanks
Vladimir

Jbriggeman

I have a 2017 Lexus RX-350 that has experienced the engine droning noise at 1500-1700 rpm. Have put up with this annoying noise since purchased new in September 2016. Numerous visits to the Lexus Service Department with NO relief. Finally in 2018 Lexus came out with

L-SB-0003-18 Rev1 January 25, 2018
Exhaust Drone at Takeoff or Under Light Acceleration

I had this performed in August of 2020. IT NOT ONLY DID NOT FIX THE EXHAUST DRONING.... IT GOT WORSE.

I am thoroughly disgusted with this vehicle and this failed attempt to fix the problem. Either the service center did not perform the entire SB - OR - this isn’t a properly designed solution. The noise is at 1500-1700 rpm which coincidentally is the engine speed at approximately 35-40 mph and also at 65-70 mph, two speeds that are used most of the time in city and on highway. To pay this price for a supposedly quality automobile is frustrating and embarrassing. When I have other passengers in the car they comment about this droning noise.

LEXUS - IF YOU ARE LISTENING - DO YOU EVEN CARE?
if so, please fix this.
if not, please advise so I can go buy a Mercedes, BMW, or am Infinity.
By the way, when my daughter was looking for a new car, she refused to consider a Lexus because of this droning noise. She ultimately paid much less and purchased a MUCH nicer Infinity, with more options, a much better layout of controls on dash and console, for considerably less money....

Buyer BEWARE, do NOT purchase a Lexus.

gnguyen

This is exactly the same thing I went through, but first with a 2019 450H that they refused to acknowledge the issues, then 2nd with the trade in for a 2019 RX350. I'm pretty sure the dealers executed the TSBs correctly, but these TSBs were not meant to be real fixes (more like minor mitigations). A lot of owners in this thread experienced similar issues and the TSBs made it worse. I now have the hesitation, drone and excessive vibrations; my 14 yr old Tacoma drives better than this. I'm pretty disgusted with this vehicle and Lexus will continue to ignore us as long as sales are good. I'm sure they are well aware of the issues, and the bean counters were able to justify to continue producing this crappy vehicle and not fixing the issues since they were discovered in 2016. All the loaners I've driven (5 of them) ranging from 2018 to 2021 have these issues with varying degree of severity. I've managed to convince 2 relatives of mine to stay away from Lexus plus they've lost a lifetime fan from me.

Buyer BEWARE!

Jbriggeman

You are right. They do not care. I have bought my last Lexus even though a friend of mine is a sales manager at Westside Lexus in Houston where I purchased this car. I know I have personally steered at least 10-12 friends and relatives away from buying a Lexus, including 2 daughters and even my ex-wife.

While Lexus is obviously doing just fine without my business... they will do without my business forever. Thanks for your reply. One daughter has a Ford Explorer and another daughter and my ex wife both have an Infinity. All 3 cars are light years ahead of Lexus on console and dashboard layouts, quality of build and quality of service. Thanks again for your reply.

toyotaguy2

This is a very tricky problem to solve,and I suspect only Toyota/Lexus knows the solution. I have a Highlander with the same drone issue,and I have not been able to solve it despite installing a custom exhaust system consisting of Magnaflow mufflers, Vibrant Performance resonators, Walker Y-Pipe and Weapon-R headers. Noise is still there.

Jbriggeman

Lexus USED to build a quality automobile but they haven’t for a number of years, choosing instead to rest on their laurels and reputation from a number of years ago. No more. Lexus builds a 3rd rate car that is average at best. Their engineers do NOT have the talent to solve this problem. It can be solved. We went to the moon 51 years ago. I have read of some owners that found solutions for this issue and fixed it themselves. Lexus/Toyota is asleep at the wheel and don’t have the talent.

This vehicle also had the gas tank rattle when filled up and it took them 3-4 years to solve what a shade tree mechanic could solve on a weekend. Same here.

Lexus Isn’t the car or the company they used to be and will lose market share eventually. Probably to Ford and General Motors. LOL. I know I’m done with them forever.

NickSP

Is this drone issue only on the 4RX? I have a 3RX 450 and don't notice this or I'm going deaf.

dibl

Yes. You have a different engine and transmission.

Jbriggeman

I don’t know since I haven’t driven the 450 but haven’t heard or read about it. If you had it you would hear it, trust me. It is so obnoxiously present that every passenger I have ever had in my car has heard it and commented about it. It is in the exhaust system and I’m not convinced it isn’t in the baffling in one of the components or a connection to the frames. I can duplicate it at a stop while holding the brakes and increasing the rpm to the 1500-1700 range. It is obvious. Hard to avoid that rpm range since it coincides with 35-40 mph in city and 65-70 on highway.

vmoldovan

I was able to achieve some success, about 50% of droning is gone!
Now when an engine goes over 1700 RPM, it is less noticeable, when resonance spikes, and it sounds closer to what it sounds at 1600 or 1800. But I still can hear it.
I also secured heatshields. I hear some rattle still so need to go under again.
Those heat shields should not rattle like that. It is a shame Lexus.

I have latest ideas to try.
The next time I am in a store, I'll buy two more clamps, remove the factory weight, which is mounted on the left of my picture, and mount it next to this one, adjacent to the same position, the same side.
Another idea is to mount factory weight on the other side of these same clamps I added.
Previously I removed the factory weight, just to try, and that produced no discernable difference that I could hear so my thought is that it is useless where it is mounted.

Today I also bought a creeper and a week ago a pair of ramps to make it easier to get under. It is a winter here so my floor is dirty so a creeper will help.
This now is a part of my "enjoyment" of 4-year-old Lexus I bought a year ago, Lexus certified.
That is my update.

Thanks
Vladimir

Jbriggeman

To answer a previous question by someone else in this thread, my vehicle was very quiet for about 1,000 miles and one day while accelerating on entrance ramp to enter highway the noise began all of a sudden. SO it might or might show up on a test drive. I wouldn’t buy a new one if it was as quiet as a church mouse on a test drive for fear it would develop after I took possession of it. It just isn’t worth it. Go with anything but a Lexus. They just no longer have the quality they once did and worse yet, they no longer care about quality or service. Too many threads on this forum as well as other forums and social media. It is so frustrating to have paid a premium for a third rate automobile. The L doesn’t stand for Lexus anymore. It stands for Lousy.