rlx015

Recently I had an opportunity to drive 2023 BMW X5 x40i for a few days while putting around 1600-1700 miles, and comfortability, quality and serenity of driving it was an absolute pleasure.
Super quiet inside, well insulated, no weird noises, no trim rattles, superb suspension, lovely modes, etc. All in all, amazing quality driving experience...

Being back home and driving my RLX-SH again, certainly showed me some highlights on why I like RLX SH, but also amiplified one big ticket item for me: noise and how not so insulated RLX SH truly is.
Sure it cannot be compared with BMW, but in general speaking, I feel that RLX-SH noise levels are far beyond than what they should be all different brands considered.

I'll start first and say that regardless of the recent BMW X5 driving experience, I do not like noise of RLX-SH while driving in lower speeds than 20-25mph, noises of slowing down are too loud, etc.

How do you feel about noise in RLX-SH so far, and does it annoy you?

mrgold35

I usually have the Krell audio on for background and just learned to tune out road, engine, and wind noise being a Honda and now Acura owner for +25 years. I'll say my RLX with OEM tires and aftermarket rims (no noise reducing resonator band on aftermarket rims) has the lowest noise levels with my 19 MDX and then 11 MDX right behind. The 08 RDX was extremely loud with roar of road noise and my 06 TSX did quiet down a few noticeable decibels when I switched to Conti DWS tires. Both of my MDXs had 20" aftermarket rims with Conti DWS 06 tires. Planning to switch to Conti DWS 06+ tires on my RLX in a year or two.

I do notice more mechanical or TMU noise from the rear with the RLX I don't hear with my 19 MDX Sport Hybrid at low speeds.

rlx015

Great info - thank you for sharing.
TMU noise at lower speeds almost reminds me when wheel bearings start to go bad

hondamore

It is really hard to compare the ride quality of one brand of car vs another unless you drive them one immediately after the other over the same road, with the same tires, in the same weather conditions etc.

Overall, I have been very pleased with the ride quality of the RLX Sport Hybrid although I do notice more road noise when the tires are cold. I also have an early version of the Sport Hybrid (2014) and I believe they made some small improvements to the front suspension in subsequent model years. Comparing the ride to a BMW, my sense is that the BMW puts more emphasis on max handling and thus are a bit harsher riding whereas the RLX is "floatier" and more limo-like prioritizing comfort over at-the-limit handling and relying more on the Sport Hybrid technology to improve cornering.

Just my two cents.

hondamore

I found a couple of items in the owners manual regarding low speed noises in the Sport Hybrid:

1. Sounds Unique to the SPORT HYBRID SH-AWD® System
When you first start driving this vehicle, you likely will hear some unfamiliar sounds, particularly when you first turn on the power system, while driving, and just after parking. Some of these sounds are unique to this vehicle‘s powertrain, fuel, and climate control systems; others are similar to sounds generated by conventional automobiles that typically are masked by louder noises absent from a vehicle of this design. These sounds are not a cause for concern, and you will soon recognize them as normal and thus be able to detect any new or unusual noise should one develop.


2. Acoustic Vehicle Alerting System
Alerts pedestrians when a vehicle is propelled solely by electricity, approaching at speeds around 12 mph (20 km/h) or less.
​​​​​​
The Acoustic Vehicle Alerting System makes a funny sound when you are going slow in EV mode with the intention being so that pedestrians can hear the car coming (because it it so quiet relative to when the Ice is operating). It is very hard to describe, but sounds sort of like someone holding down keys on an electric organ. I believe there is a button to turn off the AVAS, but it defaults to on every time you start the car. I just thought of this as one of the possible reasons for "weird noises" when driving very slowly in EV mode.

EDIT: I checked the manual again and the AVAS button to turn off the noise in EV at low speed may only be in the Canadian models. The button is with the Traction Control button etc down by your left knee.

mrgold35

The Acoustic Vehicle Alert sounds the same for both of my Acura Hybrids. I call it my UFO sound because it makes a whirling Sci-Fi sound at low speeds. I'm really not sure why Acura or any EV maker would use any low speed sound other than a car I.C.E. engine sound at low speeds? The sound is OK; but, I would rather have Porsche Carrera GT V10 or GM V-8 in 5.7L/6.2L or 7.0L as an option.

rlx015

Noise I am hearing sounds rather something like coming from TMU, not the Acoustic Vehicle Alert... If I had to compare it to automotive noises known to most of people is very similar to when a wheel bearing is going bad.
I know it is not the wheel bearing because I hear it the most between 10-25mph (when slowing down to traffic light, stop signs, etc.)... My oil coming up soon anyway so I will ask dealer to perform drive check and see if they see anything off with it. I am almost tempted to ask them to do a TMU fluid flush (again)... I had it done about a year/year and a half ago at another dealer (that screwed my spoiler install) so chances are they also screwed something with what fluid they are using for TMU... urgh... when I remember: I had to tell the "service manager" to check manual page X to convince him that RLX Sport Hybrid did not have "differential" but TMU (twin-motor unit)...

hondamore

My apologies rlx015, I wasn't questioning the noise you are hearing but rather listing other "unusual" noises from the Sport Hybrid that are completely normal. If you have an unusual sound coming from the TMU, then it definitely should be investigated.

Sadly, with the RLX Sport Hybrid being so rare, mechanics rarely work on them and can be prone to making assumptions (eg. same oil capacity as the PAWS version, same Transmission fluid as all other Acuras) that can have serious consequences.

rlx015

Ah, no apologies needed at all! I think your post reminded me to include information what made me post this thread lol so wanted that on the "books" when people read it, if they relate so they can comment as well
Thank you!!

mrgold35

I forgot to mention additional cabin noise from the ventilated seats at low mph on the RLX I don't hear with my 19 MDX.

rlx015

Wanted to bring this to life as well in the case some people missed it (or never searched for it).
In terms of noise of the cabine interior when driving at higher speeds, there may be somewhat of a window noise on driver side that almost feels like it is right next to the driver's ear.
To improve the weather strip intent, installing a piece of "D" tape (covered in more detail in this thread Noise DIY fix for wind noise at high speeds.

I would say quietness of the car inside the cabin when driving over 70mph has improved fairly noticeably. I'd say from 7/10 into 8.5 or 9/10...

rlx015

I figured I provide an update of a sort of "noob" mistake when thinking that RLX was not insulated.
After 2.5 years of getting my RLX I finally changed my tires. It still had factory oem original tires, and I went with Conti ExtremeContact DWS6+ .... aaannnddd... this is now a DIFFERENT CAR 100%...
So much of noise was resolved by changing tires, and realizing that Michelin had to be run-flats and were the sole culprit of the noise, and weird 10-15-20mph motion making stupid noise that really got amplified the older original tires were.

Now, I feel like I got a new car how better it is lol ...

mrgold35

I changed my 19 MDX OEM 245/50/20 to 275/45/20 Conti DWS 06+ at 42,000 miles (+50,000 miles now). No impact on my MDX sport hybrid combined mpgs; but, improved lower road noise, more planted handling, better braking feel, and I like the overall feel. Planning to change my RLX to Conti DWS 06+ next year (only 32,000 miles on the RLX). I live in the southwest high desert with extremes ranges with temp, rain, and snow (sometimes all in one road-trip). Conti DWS 06+ works for me because it covers a wide range of driving conditions without having to switch between summer/winter tires.

andysinnh

Welcome to the Conti upgrade club! Wife is still happy with her DWS 06+ tires after having them for over a year. Wear is negligent and handling is still top-notch. The RLX now has winter sneakers on it, so you can really tell how well the Conti's work when you don't have them :-)

neuronbob

Wait. You mention Michelin runflats? The OEM tires for the RLX are not runflats.

Even so: I was satisfied with the Contis on my RLX SH. Nice and quiet, no effect on fuel economy. The person who bought my SH is surely enjoying the brand new tires I installed only six months before, and which had only about 2k miles on them.

rlx015

Hmmm... now I am wondering if they were OEM... because they were definitely run-flats... so maybe previous owner got them since there was no spare tire coming with the car?
Anyway, it is a good riddance to be quiet honest