Suspension Rattle Anyone? - RLX

Thread Tools
 
Search this Thread
 
Old 12-05-2014, 09:14 PM
  #201  
Three Wheelin'
 
holografique's Avatar
 
Join Date: Jul 2008
Location: Atlanta, GA
Age: 49
Posts: 1,793
Received 937 Likes on 487 Posts
I take that back...I will be test driving a Hybrid soon when it arrives at my local dealer (the one you mentioned George was sold before I was able to give it a test drive, and another one is enroute but also already sold).

From there I will guage what the difference is in the two models and if it feels better and more firm yet padded than the P-AWS model, then I will definitely get one come 2016.

Geez, you would think with all the other luxury sedans out there offering adjustable suspensions, you'd think Acura would have this. Seriously, that would solve this whole thing all together. Single sedan model, variable suspension to meet the varying needs of different drivers. Heck, make it an option and charge more for it just like all the other brands do. I'll gladly pay for that type of added feature and flexibility in the car.
Old 12-05-2014, 10:42 PM
  #202  
Instructor
 
flagship's Avatar
 
Join Date: Nov 2014
Posts: 112
Received 24 Likes on 14 Posts
Originally Posted by holografique
Well...good news, bad news...

Bad news: nothing has changed regarding the overall "ride comfort" of the vehicle when dealing with less than stellar road conditions (bumbs, potholes, inner-city driving, etc). Feels pretty much the same prior to the TSB repair. It still exhibits the same jarring shocks to the chassis and the steering when hitting road conditions that otherwise are handled just fine by the TLX, MDX, RDX, and ILX (I've had all of these as loaners, including my wife's ILX on the same roads I drive to and from work.)

Good news: the loose "rattle" "jumbly" sound is gone. you don't get that sound of the chassis being lose or "stuff" jumbling around anymore.

The service documentation clearly states that there is a "faulty valve" in the suspension that is at fault for the "noise/rattling". No other details provided.

At this point, I've come to the conclusion, that I'm just going to have to live with the fact that this is how this car rides. Whether it was intentional or a design mistake, I honestly don't have the time to care anymore. Too many other important things in life going on right now. I lease the car, I don't plan to buy it either at the end of the lease, so at this point I just don't care. We'll see if Acura does anything to change or address this come 2016, for what I feel is a poorly designed suspension for what should be a "luxury ride" for a car at this price. If not, then I'll most definitely be looking to make a move when my lease is up. A6, E350 or a GS. I loved the TLX and it's a superb car, but it's too small for what I want and doesn't carry the additional "luxury" that I want.

I really hope Acura figures it out.
Good attitude.
Honda/Acura quality and control sadly just does not seem what it was. I would not doubt any reported issue on any model could be in the design, quality or a vehicle specific anomaly. The FIT in Japan had five recalls, the RLX have botched suspensions, mpg is below promised. Bad infotainment on top of the line car. LOWEST score in consumer reports. Low mileage achieved per promise on website. Did we ever learn why the RLX hybrid was delayed? Bumps should not be an issue on an RLX. What would you consider if you were to replace it now. It is good you leased. I never considered in the past but may need to for "safety".
Old 12-06-2014, 09:07 AM
  #203  
Grandpa
 
George Knighton's Avatar
 
Join Date: Dec 2003
Location: Virginia, Besieged
Age: 68
Posts: 7,596
Received 2,609 Likes on 1,475 Posts
Originally Posted by holografique
I
Geez, you would think with all the other luxury sedans out there offering adjustable suspensions, you'd think Acura would have this.
This doesn't help with your individual situation, but if it helps give any hope for the future, they're asking a lot of questions about what buyers would prefer.

They seem to have a faction who want to go the Mercedes route, with an air suspension, and a faction who want to go with a wider rollout of the current Honda IDS system, which uses magnetic fluid in the dampers to firm it up when the driver wants it firmed up.

The adjustability built into the TLX system is modification of the IDS system that they already knew to produce, but they seem to think that the purchasers at the level of a Legend might want an air suspension that is self-leveling in addition to providing firmness when you want it, plus the ability to raise the suspension up at all four corners on the off chance you might have to take off cross country after poachers.

0_0

My problem with the Mercedes air suspension is that it is not giving the driver an instant attitude correction...it's a very small but perceivable fraction of a second.

When you add that delay to the delay and odd (for some people) LSD-like working of the two rear motors when you're driving all out, and then add to that the possibility that the gasoline motor has to start up to do what you've begun to ask the car to do, it might add up to too many little fractional delays, and give the driver the impression that the car's hunting for direction, height and attitude.

They'll figure it out, but right now I don't think they know if they really can deal with an air suspension.

A car that I just had to own before I died was the 6.3 litre der Grosser Mercedes. Tremendous car in so many ways, but just awful in that it nowhere lived up to its reputation as a great driver and in typical old Mercedes fashion it was just a hole in the road you dumped your money into.

Anyway, this car had the very first Mercedes attempt at air suspension.

The delay was so long that if you were driving all out and went into a corner full tile, it could be as much as 1/4s before the air suspension (it was mechanical, no electronics) picked its final attitude.

So, basically, counter steering to compensate for sudden oversteer became a way of life, and presented the most alarming spectacle for people watching.
Old 12-06-2014, 09:13 AM
  #204  
Grandpa
 
George Knighton's Avatar
 
Join Date: Dec 2003
Location: Virginia, Besieged
Age: 68
Posts: 7,596
Received 2,609 Likes on 1,475 Posts
Originally Posted by holografique
From there I will guage what the difference is in the two models and if it feels better and more firm yet padded than the P-AWS model, then I will definitely get one come 2016.
Cars dot com says there are still some scattered around the country, but I'm afraid that if you want one now instead of waiting, it's going to involve a bit of a drive for you, and a need to have all the finances straight ahead of the drive.

The Sport Hybrid is far from perfect and I could make you wonder about my choice if I told you about all of them.

(Why the bloody heck do voice controls not work any more when you have the Power Distribution Meter showing in the 8" screen!!??)

But it's still a great car, the best car I've owned as a daily driver in a long time, and it is a car that I can very well imagine holding onto for a long 100,000-plus mile run.

Unless, of course, that danged dealer calls me about the first NSX-Advance he gets on whatever Sunday it's going to be, with the usual promise that they'll "work it out" for me.

:-/

"Working it out" usually entails spending unwise sums of money.
Old 12-06-2014, 10:57 AM
  #205  
Senior Moderator
 
neuronbob's Avatar
 
Join Date: Nov 2001
Location: Cleveland area, OH
Posts: 20,015
Received 4,612 Likes on 2,193 Posts
Originally Posted by George Knighton
Unless, of course, that danged dealer calls me about the first NSX-Advance he gets on whatever Sunday it's going to be, with the usual promise that they'll "work it out" for me.

:-/

"Working it out" usually entails spending unwise sums of money.
Funny, my salesman had a similar conversation with me as I was picking up my RLX. In my case, though, the NSX is likely to be far above my pay grade. Still putting muy dinero in my son's college fund, ya know.

No suspension rattle in my RLX.

....and for holografique, 101 Sport Hybrids nationwide, unchanged from my last check about a week ago, 21 of them Advance.

I agree with you on the adjustable suspension. Honda just needs to borrow the Magnetic Ride shocks from Delphi Automotive...well, I mean, Beijing West Industries, which now owns the tech. Works well on my Cadillac, instantaneous response, the ride quality on the stock 19's is less harsh than, yet just as responsive as, the RLX.
Old 12-06-2014, 12:32 PM
  #206  
Three Wheelin'
 
holografique's Avatar
 
Join Date: Jul 2008
Location: Atlanta, GA
Age: 49
Posts: 1,793
Received 937 Likes on 487 Posts
^ great input guys, I really appreciate it.

Very interesting comments on the future of Honda/Acura suspension. I agree with everything you're saying George. IDS versus air-suspension is a manner of detail above what I am looking for, which is simply a great high-tech luxury car that I can adjust how it "feels" based on my "mood" when driving the car.

If the current IDS system that I experienced in the TLX is any indication of what they can do to the future of the RLX, then I can already say I will be MUCH happier than how things are now in the 2014 P-AWS RLX.

At the moment I have definitely made up my mind that IF I get a Hybrid, it won't be until the MMC comes out. So whatever existing ones are out there are off my radar, other than to test drive one to get a feel for the power-plant and the SH-AWD action and hopes that they get "everything else" right in the MMC update.

For now, I'll try to forget that I pay $980 a month for a car that can't handle road conditions better than most cars that cost far less...:|
Old 12-06-2014, 12:36 PM
  #207  
Three Wheelin'
 
holografique's Avatar
 
Join Date: Jul 2008
Location: Atlanta, GA
Age: 49
Posts: 1,793
Received 937 Likes on 487 Posts
oh...and an NSX...yea, that would be amazing, but likely off my pay-grade for sometime.

But who knows, by 50, I might be one of those gray-haired guys I see driving hot luxury sport cars and say to myself....one day...
Old 12-07-2014, 05:06 AM
  #208  
Instructor
 
sooththetruth's Avatar
 
Join Date: Aug 2014
Location: Saint Simons Island, GA
Posts: 160
Received 104 Likes on 50 Posts
Originally Posted by neuronbob

I agree with you on the adjustable suspension. Honda just needs to borrow the Magnetic Ride shocks from Delphi Automotive...well, I mean, Beijing West Industries, which now owns the tech. Works well on my Cadillac, instantaneous response, the ride quality on the stock 19's is less harsh than, yet just as responsive as, the RLX.
Ferrari has borrowed that system, for ALL their elite super cars.

The point of the these new systems is the continuous adjustment of suspension based on road conditions, based on inputs that allow variances in suspension in hundredths of a second. So the magnetic system is really an infinitely variable suspension that will take on a stiffer dynamic when taking a corner hard, and soften to a smooth cruiser while on the highway. No need to choose an "attitude".

This suspension is only a $1000 stand alone options on Cadillacs, and though it doesn't get a lot of press, I think it THE suspension to try. Cadillacs are routinely described now as having a better chassis, and better body control than BMW's. Cadillac is falling short with some of their engines (and I think their looks are as polarizing as the Acura "beak").

I have found that with cars that have multiple suspension settings I will find myself playing endlessly with the different settings, and when finally tired out I will leave it on the softest setting. Of course, I am OVER 50, gray haired (and bald), and have no desire to drive a sports car...because they're usually low. I do take a turn aggressively pretty often, though, hence the beauty of a suspension that is ready when I am.
The following 3 users liked this post by sooththetruth:
holografique (12-07-2014), neuronbob (12-07-2014), wstr75 (12-07-2014)
Old 12-07-2014, 10:57 AM
  #209  
Three Wheelin'
 
holografique's Avatar
 
Join Date: Jul 2008
Location: Atlanta, GA
Age: 49
Posts: 1,793
Received 937 Likes on 487 Posts
^ you nailed it. as much as an adjustable suspension settings sounds attractive, ultimately I just want the car to respond appropriately depending on how I feel like driving. whether I'm cruisin, rushed for a meeting, or playing wannabe speedracer, I just want the car to always feel good, solid, and confident.

I felt this in the TLX, so I have hopes that Acura can get it right eventually. Get Matt on the damn RLX team and fix this cars future.
Old 12-07-2014, 11:51 PM
  #210  
Racer
 
bronx1480's Avatar
 
Join Date: May 2011
Location: bronx ny
Age: 43
Posts: 280
Received 28 Likes on 16 Posts
Originally Posted by holografique
^ great input guys, I really appreciate it.

Very interesting comments on the future of Honda/Acura suspension. I agree with everything you're saying George. IDS versus air-suspension is a manner of detail above what I am looking for, which is simply a great high-tech luxury car that I can adjust how it "feels" based on my "mood" when driving the car.

If the current IDS system that I experienced in the TLX is any indication of what they can do to the future of the RLX, then I can already say I will be MUCH happier than how things are now in the 2014 P-AWS RLX.

At the moment I have definitely made up my mind that IF I get a Hybrid, it won't be until the MMC comes out. So whatever existing ones are out there are off my radar, other than to test drive one to get a feel for the power-plant and the SH-AWD action and hopes that they get "everything else" right in the MMC update.

For now, I'll try to forget that I pay $980 a month for a car that can't handle road conditions better than most cars that cost far less...:|
i thought i was the only one paying 980 a month
Old 12-08-2014, 05:16 AM
  #211  
Instructor
 
mgalbr22's Avatar
 
Join Date: Mar 2014
Location: Cincinnati, oh
Posts: 152
Received 21 Likes on 12 Posts
Agreed

Originally Posted by holografique
Well...good news, bad news...

Bad news: nothing has changed regarding the overall "ride comfort" of the vehicle when dealing with less than stellar road conditions (bumbs, potholes, inner-city driving, etc). Feels pretty much the same prior to the TSB repair. It still exhibits the same jarring shocks to the chassis and the steering when hitting road conditions that otherwise are handled just fine by the TLX, MDX, RDX, and ILX (I've had all of these as loaners, including my wife's ILX on the same roads I drive to and from work.)

Good news: the loose "rattle" "jumbly" sound is gone. you don't get that sound of the chassis being lose or "stuff" jumbling around anymore.

The service documentation clearly states that there is a "faulty valve" in the suspension that is at fault for the "noise/rattling". No other details provided.

At this point, I've come to the conclusion, that I'm just going to have to live with the fact that this is how this car rides. Whether it was intentional or a design mistake, I honestly don't have the time to care anymore. Too many other important things in life going on right now. I lease the car, I don't plan to buy it either at the end of the lease, so at this point I just don't care. We'll see if Acura does anything to change or address this come 2016, for what I feel is a poorly designed suspension for what should be a "luxury ride" for a car at this price. If not, then I'll most definitely be looking to make a move when my lease is up. A6, E350 or a GS. I loved the TLX and it's a superb car, but it's too small for what I want and doesn't carry the additional "luxury" that I want.

I really hope Acura figures it out.
After driving the car for a week and soliciting also my wife's opinion, we are convinced that the condition has not been corrected-certainly not in the rear since that was not part of the tsb repair.
I also noted that the dealer deflated my tires, which they did the last time they worked on the suspension. ( I always keep them inflated to the correct level of 35 in the front and 33 in the rear.) When I picked up the car after the tsb repair, they were all at 30-32, most closer to 30. Clearly, they believe this helps mask the noise and vibration-or acura has advised them to do this. Makes no sense and is, frankly, dishonest.
However, I do not and will not accept this for 2 more years of my lease and $550/month. I am proceeding with the lemon law suit that I filed after waiting nearly a year for any acition by acura to address this defect.
The following 2 users liked this post by mgalbr22:
miner (12-08-2014), sooththetruth (12-08-2014)
Old 12-08-2014, 08:49 PM
  #212  
Instructor
Thread Starter
 
KenRLX's Avatar
 
Join Date: Jan 2014
Posts: 102
Received 77 Likes on 42 Posts
I did get the 'fix' done for the front suspension. Subjectively, the suspension does feel a bit 'softer', but not much. The really really annoying rattles at low speeds over small bumps are gone (or reduced quite a lot), but when the road gets a bit more uncontrolled and the suspension needs to move more rapidly, I still hear suspension noise. I have rented a lot of mid and lower range cars over the past several months - NONE have this kind of uncontrolled type of sound.
When new tires are needed, I'll seriously pursue 18 inchers, or if they'll fit, 17 inchers. (Or if anyone has some 18 inchers needing a new home, let me know)
The slightly taller profile will help a lot.. for instance check the inflation pressure in the RLX manual for the 19 vs 18's - a significant difference. I think perhaps the stylists got the deciding vote over the engineers putting on 40 series 19 inch tires on such a stately vehicle.
I also noted the low tire pressure after the work was done - And it is noticeable in the ride - but my observations are that it doesn't really quiet anything - though that may be some of the intent by Acura/dealer.
Its a shame that given the low volume of the car, I can't just go out and get a good set of Monroe's (or even Bilsteins) to put everything right.
And as I heard from others in the thread - I am resigned that it is what it is... maybe the 2016's will get it right and I can get replacement parts by then.


At least it went from teeth gritting anxiety at every little bump to something noticeably less severe.


And given what Acura says as a fix, it seems obvious they rediscovered the damper 'loose lumber' noise problem published by SAE back in '09 and by others.
The following 3 users liked this post by KenRLX:
mgalbr22 (12-09-2014), miner (12-09-2014), wstr75 (12-08-2014)
Old 12-09-2014, 05:24 AM
  #213  
Instructor
 
mgalbr22's Avatar
 
Join Date: Mar 2014
Location: Cincinnati, oh
Posts: 152
Received 21 Likes on 12 Posts
Originally Posted by KenRLX
I did get the 'fix' done for the front suspension. Subjectively, the suspension does feel a bit 'softer', but not much. The really really annoying rattles at low speeds over small bumps are gone (or reduced quite a lot), but when the road gets a bit more uncontrolled and the suspension needs to move more rapidly, I still hear suspension noise. I have rented a lot of mid and lower range cars over the past several months - NONE have this kind of uncontrolled type of sound.
When new tires are needed, I'll seriously pursue 18 inchers, or if they'll fit, 17 inchers. (Or if anyone has some 18 inchers needing a new home, let me know)
The slightly taller profile will help a lot.. for instance check the inflation pressure in the RLX manual for the 19 vs 18's - a significant difference. I think perhaps the stylists got the deciding vote over the engineers putting on 40 series 19 inch tires on such a stately vehicle.
I also noted the low tire pressure after the work was done - And it is noticeable in the ride - but my observations are that it doesn't really quiet anything - though that may be some of the intent by Acura/dealer.
Its a shame that given the low volume of the car, I can't just go out and get a good set of Monroe's (or even Bilsteins) to put everything right.
And as I heard from others in the thread - I am resigned that it is what it is... maybe the 2016's will get it right and I can get replacement parts by then.


At least it went from teeth gritting anxiety at every little bump to something noticeably less severe.


And given what Acura says as a fix, it seems obvious they rediscovered the damper 'loose lumber' noise problem published by SAE back in '09 and by others.
They may have rediscovered the loose lumber paper but have failed to fully and accurately analyze the root cause of the problem and/or have failed to implement the proper, comprehensive permanent corrective action for the defective strut design.
Old 12-09-2014, 06:53 PM
  #214  
Three Wheelin'
 
holografique's Avatar
 
Join Date: Jul 2008
Location: Atlanta, GA
Age: 49
Posts: 1,793
Received 937 Likes on 487 Posts
Originally Posted by KenRLX
I did get the 'fix' done for the front suspension. Subjectively, the suspension does feel a bit 'softer', but not much. The really really annoying rattles at low speeds over small bumps are gone (or reduced quite a lot), but when the road gets a bit more uncontrolled and the suspension needs to move more rapidly, I still hear suspension noise. I have rented a lot of mid and lower range cars over the past several months - NONE have this kind of uncontrolled type of sound.
When new tires are needed, I'll seriously pursue 18 inchers, or if they'll fit, 17 inchers. (Or if anyone has some 18 inchers needing a new home, let me know)
The slightly taller profile will help a lot.. for instance check the inflation pressure in the RLX manual for the 19 vs 18's - a significant difference. I think perhaps the stylists got the deciding vote over the engineers putting on 40 series 19 inch tires on such a stately vehicle.
I also noted the low tire pressure after the work was done - And it is noticeable in the ride - but my observations are that it doesn't really quiet anything - though that may be some of the intent by Acura/dealer.
Its a shame that given the low volume of the car, I can't just go out and get a good set of Monroe's (or even Bilsteins) to put everything right.
And as I heard from others in the thread - I am resigned that it is what it is... maybe the 2016's will get it right and I can get replacement parts by then.


At least it went from teeth gritting anxiety at every little bump to something noticeably less severe.


And given what Acura says as a fix, it seems obvious they rediscovered the damper 'loose lumber' noise problem published by SAE back in '09 and by others.
My tire pressure was set a good bit higher than normal after I picked mine up from the suspension TSB (39F/38R cold) and after setting it back down to my preferred pressure (35F/34R cold), I have noticed that it is somewhat "softer" than before at the same settings. I ran my normal route into work today and deliberitely hit every bump/pothole/metal plate I could find (some I know well, others were new) and I could tell a bit of a difference, but overall still unsettling and vastly different from my experience with the TLX. Pretty much on par with how Ken has explained it.

So while it's still unacceptable for a car of this class, it looks like soke progress is being made.

Sorry to see your experience is not the same mgalbr22.
The following users liked this post:
mgalbr22 (12-10-2014)
Old 12-12-2014, 06:37 AM
  #215  
Instructor
 
mgalbr22's Avatar
 
Join Date: Mar 2014
Location: Cincinnati, oh
Posts: 152
Received 21 Likes on 12 Posts
rlx/tlx suspension comparison

Originally Posted by holografique
My tire pressure was set a good bit higher than normal after I picked mine up from the suspension TSB (39F/38R cold) and after setting it back down to my preferred pressure (35F/34R cold), I have noticed that it is somewhat "softer" than before at the same settings. I ran my normal route into work today and deliberitely hit every bump/pothole/metal plate I could find (some I know well, others were new) and I could tell a bit of a difference, but overall still unsettling and vastly different from my experience with the TLX. Pretty much on par with how Ken has explained it.

So while it's still unacceptable for a car of this class, it looks like soke progress is being made.

Sorry to see your experience is not the same mgalbr22.
thought this would be interesting material for this thread. holographic posted this in late nov, prior to the tsb repair he references above. it is an excerpt from his overall comparison of the two cars

"I honestly don't know how to write this last paragraph without going into a huge tirade. But all I can say is Acura really F'd up the suspension in the RLX P-AWS. After being in this loaner TLX now for over a week and driving the EXACT same routes I take too and from work, and knowing EVERY SINGLE bump, pot hole, etc. etc. to avoid when driving my RLX, I wonder how I do it. The TLX takes everything with absolute 100% confidence and recovers with not a single after-shock, rock, rattle, bobbing, bounce, etc. What was once a constant battle to avoid anything sub par on the road and having to pay constant attention to the road conditions has now just turned into a "driving" with no worries.

The TLX suspension has a very solid and confident "thud" with an immediate recover when hitting a bump or even large pot-holds. "thud" and recover. 1, 2, that's it. And that's if I even feel anything at all going right over areas with no disruption at all, whereas in my RLX it's a disaster. And don't think that the TLX is all super spongy, it has a really solid feel to the suspension. It hugs the road when you need it to, but instantly soaks up anything and everything without a single question. On the other hand the RLX hits anything extremely hard, loud, and with a physical shock in the steering wheel like the car is going to break or some serious damage is being done to the vehicle. You feel everything in the chassis of the car and you hear it. You don't get a muted "thud". You get loud "CLANK" "KLUNK"....as if the car was being slammed hard. It really is that bad, and that's why I'm at the point where I really don't like driving the car downtown at all. I'm constantly having to bob and weave and slow down and speed up and bob and weave again just to avoid feeling like the car is going to break, it's pathetic. It just feels like the car doesn't even have shocks at times. I just don't get it. I really don't. And it really upsets me because if the RLX handled the road half as good as the TLX does, it would make the driving experience just that much more enjoyable. As long as you keep the RLX on solid roads or highways, it drives and feels amazing, but seriously, Acura needs to figure this out. A $60k luxury sedan should not drive this like. Period. No excuses. I don't care what anyone has to say. The car has a serious defective design issue with the suspension and it needs to be resolved. And I'm at the point where if this is something that remains the same come 2016 when I turn in my lease and look at the MMC, I will be walking to another brand if they don't address this. I really like the TLX, but it doesn't carry the same level of sophistication and luxury that I want in a car, that the RLX does carry. But I also cannot deal with this suspension issue again. "

It continues to baffle and infuriate me how poorly Acura designed the suspension for the rlx and how long they have taken to make any effort to correct it. the front suspension tsb repair is inadequate, and they have issued nothing for the rear, which has the same "loose lumber" defect.
Old 12-12-2014, 08:36 AM
  #216  
Three Wheelin'
 
holografique's Avatar
 
Join Date: Jul 2008
Location: Atlanta, GA
Age: 49
Posts: 1,793
Received 937 Likes on 487 Posts
Originally Posted by mgalbr22
It continues to baffle and infuriate me how poorly Acura designed the suspension for the rlx and how long they have taken to make any effort to correct it. the front suspension tsb repair is inadequate, and they have issued nothing for the rear, which has the same "loose lumber" defect.
I think George confirmed the issue for us just recently in another post "Things I learned today", where he stated that the suspension was originally designed for the SH-AWD, which is a heavier car.

And this makes sense to me. One of the attributes of the suspension issue is that the car just seems to "bobble" and "fumble" around way too easily over the smallest bumps. As if the chassis was hollow or too light in weight, sitting on a bunch of super sensitive springs. The other attribute is just straight jarring "shocks" to the chassis when hitting potholes or other conditions that create hard angular changes in road elevarion. Without the added weight of the SH-AWD systems, the P-AWS version is simply too light and sensitive based on the single suspension design.

I equate it to being the same thing as the difference in air turbulence flying in a small CRJ/717 versus a larger 767 or A330. The added weight in larger planes causes more inertia, thus helping reduce the vibration to the fueselage and airframe caused by air turbulence, thus why you feel far less turbulence in a larger plane than a smaller plane. Same concept here with the SH-AWD vs P-AWS.
The following users liked this post:
mgalbr22 (12-17-2014)
Old 12-12-2014, 09:05 AM
  #217  
Grandpa
 
George Knighton's Avatar
 
Join Date: Dec 2003
Location: Virginia, Besieged
Age: 68
Posts: 7,596
Received 2,609 Likes on 1,475 Posts
Originally Posted by holografique
I equate it to being the same thing as the difference in air turbulence flying in a small CRJ/717 versus a larger 767 or A330. The added weight in larger planes causes more inertia, thus helping reduce the vibration to the fueselage and airframe caused by air turbulence, thus why you feel far less turbulence in a larger plane than a smaller plane. Same concept here with the SH-AWD vs P-AWS.


Sometimes the brain trust in here amazes me.

So far we have a pilot and a brain surgeon, and god knows what else.
Old 12-12-2014, 10:31 AM
  #218  
Instructor
 
2011TL's Avatar
 
Join Date: Mar 2009
Location: Northern VA
Age: 77
Posts: 218
Received 47 Likes on 34 Posts
Originally Posted by George Knighton


Sometimes the brain trust in here amazes me.

So far we have a pilot and a brain surgeon, and god knows what else.
LOL....and I'm a retired (and recovering) economist.
Old 12-12-2014, 10:55 AM
  #219  
Racer
 
Zoommer's Avatar
 
Join Date: Oct 2014
Posts: 287
Received 98 Likes on 52 Posts
Originally Posted by holografique

I equate it to being the same thing as the difference in air turbulence flying in a small CRJ/717 versus a larger 767 or A330. The added weight in larger planes causes more inertia, thus helping reduce the vibration to the fueselage and airframe caused by air turbulence, thus why you feel far less turbulence in a larger plane than a smaller plane. Same concept here with the SH-AWD vs P-AWS.
I think it also depends where you sit in the plane. A seat on top of the wing box will result in smoother ride than extreme front or back. BTW I find the A330 to be rougher ride than the 777. Just like in a car where the suspension design will affect the ride the wing design on a plane has an impact on that ride...not to start a debate on 777 vs 330.

Getting back to the suspension item....this is from Edmunds: apologies if it is a re-post. Honda has been using SACHS on Accords and Legends for a while now. To understand the various SACHS systems that are available you actually have to go through some material and then guesstimate what Honda has done with the Hybrid RLX. The combination of the two (Edmunds article + document attchment) will allow you to be better informed and also to appreciate (or commiserate) the RLX suspension.



Cheers!
2014 Acura RLX Suspension Walkaround

More Than a Dressed-Up Accord

Published: 05/02/2013 - by Dan Edmunds, Director of Vehicle Testing
Email Print




  • 2014 Acura RLX - Rear 3/4
    Our 2014 Acura RLX is the latest subject of the suspension walkaround treatment. Come back here after you read the article and click "View Fullscreen" to see big pictures. | May 01, 2013 | Kurt Niebuhr for Edmunds
22 Photos




A quick glance at the 2014 Acura RLX may cause one to believe they've just seen a dressed-up Accord with an Acura badge, but there's got to be more to it than that, right?
For one, its basic dimensions are all larger. Remember, Honda doesn't have a larger sedan in its U.S. lineup beyond the Accord, unlike Toyota, which has the Avalon. Honda seems to have decided to put an Acura badge on its larger sedan.
Compared to the Accord, the 2014 Acura RLX is 4.7 inches longer overall, has 2.9 inches more wheelbase and stands 1.6 inches wider. And its front and rear track widths (64.3 and 64.2 inches, respectively) are 1.5 inches wider than an Accord.
This last point is of interest to us because of our suspension-centric worldview. With curiosity piqued and a Rotary two-post lift standing at the ready, there's only one thing to do.
Let's lift it.

It is readily apparent that the 2014 Acura RLX differs from the 2013 Honda Accord in the very first photograph. Here we see a high-mount upper control arm that is commonly used on modern double-wishbone front suspensions. If this were an Accord we'd be staring at a MacPherson strut.

The high-mount upper control arm surrounds a coil-over spring and shock assembly. Acura says the front and rear shocks are "Amplitude Reactive Dampers," which sounds like something electronic but isn't.
I don't know the exact internal details of the valve design here, but there are many ways to mechanically alter the damping based on the actual (or expected) displacement of the shock in response to a given road input. It comes as no surprise that there's nothing external to point out here.

The double-wishbone characterization starts to fall apart when we look down below because here we find two distinct links, one of aluminum and one of steel, instead of a single L-, T- or A-shaped lower control arm.

Each of the two lower links attaches to the knuckle through its own ball joint. The steel one is the forward-pointing tension link and the aluminum one is the lateral link.

There isn't really a good agreed-upon name for this layout. Acura nominally calls it a double wishbone because conceptually it is structured like one and mechanically it behaves like one until you crank on the steering wheel.
Others call this "double wishbone with a split lower arm." This is a mutually exclusive combination of words that I nevertheless understand completely despite knowing full well that a wishbone is a one-piece structure until after Thanksgiving dinner is finished. I found one paragraph in Acura's press kit that calls it a "double wishbone, double pivot" suspension, which makes a kind of sense if you're looking at a photograph like this one.
Whatever you call it, dual ball joints such as these improve the steering geometry by moving the lower steering pivot point outboard of where it could never hope to be if only one ball joint was present. The idea is to move the steering axis closer to the center of the tire contact patch in order to reduce the so-called "scrub radius."
Many steering-related benefits spring from this. Chief among them on front-drive machines such as this is the near elimination of torque steer, which is a good thing if your 3.5-liter direct-injected V6 makes north of 300 horsepower.
But dual ball joints and dual links cost money. The 2014 Acura RLX starts at $48,500 and tops out north of $60K, so the justification to spend in this area was there.

In case you've been wondering why the steel front tension link (yellow) has that massive curve to it, here's your answer: It provides clearance for the front tire at full lock. Meanwhile, check out that nifty aluminum front subframe (black.) Looks like the oil filter might dribble on it a bit, though.

As in all other front-drive machines with sidewinder engines, the RLX's steering (yellow) does its work from behind the front axle centerline, and the stabilizer bar (green) runs right alongside.
Nearby, the lower end of the coil-over spring/shock assembly connects to the lateral link via a two-tined fork (black) that surrounds the front drive axle.

The RLX employs a hefty 33mm front stabilizer bar, but it has to be large because the motion ratio that results from its connection point midway along the lateral link is no better than 0.5-to-1, maybe less. Further out, the coil-over's motion ratio is closer to 0.8-to-1 or thereabouts.

The stabilizer bar's connecting link is curled like a pig's tail to get where it needs to go in tight quarters.

A look at the tension link's forward mounting point. The aluminum front subframe is of the perimeter variety that completely encircles the lower reaches of the engine compartment and carries the weight of the engine and transmission in addition to its steering and suspension locating duties.

The 2014 Acura RLX uses single-piston sliding brake calipers up front. The bolt-on logo plate seems to serve no other purpose than to make it look like a racier monoblock caliper to the casual observer. Acura isn't the only one involved in this sort of fakery: I saw a Mercedes-Benz C250 on the road this very morning with the exact same sort of factory-installed single-piston sliding caliper "jewelry."
Like or lame?

The 12.3-inch front rotors have the usual radial vents beneath the clamping surface, and there are additional vent (and lightening) holes down by the hub and wheel bearing.

Acura describes the rear suspension with the rather non-specific term "multilink," but we can see from here that the upper end, at least, is located by an A-shaped wishbone. We expect to see three more links down below.

The coil-over spring/shock assembly is pretty fat up top, which isn't the best approach in terms of trunk space encroachment. Depending on the audio system option you choose, the RLX offers 15.1 or 15.3 cubic feet of trunk volume. Not bad, but not fantastic either.

The coil-over shock (yellow) attaches to the upper wishbone, which makes room for the drive axles of the SH-AWD hybrid version that's coming later. But in this view the lower links are still not visib.... What the heck is that?

"That" (green) is an active toe link. Our 2014 Acura RLX is equipped with PAWS, another in a long line of odd Acura acronyms that stands in this case for Precision All-Wheel Steering. Apart from heavy equipment and forklifts, rear steering systems only move the wheels in or out a tiny amount, which means the usual sort of steering rack isn't a strict necessity. PAWS moves plus or minus 2 degrees per side (about the same as others) but it turns out, a pair of active toe links such as this can easily manage that slight amount of movement with precision.
Meanwhile, the RLX's two lower links (yellow) locate the lower end of the suspension knuckle in the usual way.

The small displacement of the PAWS actuator is reflected in the small size of its bellows (yellow.) Of course, when alignment time comes along you still adjust the static toe-in the same as usual, with an eccentric adjusting cam (green) on the inboard end.
The unit contains a fast-acting electric motor and gearset, and each actuator weighs about 7 pounds, half of which is counted as unsprung weight. If they ever build a version without PAWS they could easily substitute a pair of garden-variety fixed-length toe links here instead.
I drove the system in Japan on an Accord test mule a few months ago, and it was very effective at curbing understeer and adding stability under braking. Unlike other rack-based rear-steer systems, this design can toe both wheels in at the same time if the need arises, such as hard braking. On a small handling course at Honda's proving ground, the Accord PAWS mule was indeed very stable under heavy braking.
And that was the case even while braking into a turn. Because left and right aren't forced to move in lock step, one can imagine other sorts of subtle variations to the left and right steer angles in all kinds of situations. The understeer solution can be layered atop the braking solution, for example. This independent rear steer approach really does open up a lot of possibilities.

Here's another potential advantage that goes with the actuator-based rear-steer approach: Acura was able to leave the toe link in the forward position it seems to prefer.
In a recent suspension walkaround of the Lexus GS 350, we saw how Lexus had to locate that car's toe links behind the rear axle centerline to clear a path for its optional rack-based rear-steer system. It's hard to know for sure, but if Lexus hadn't decided to offer four-wheel steering, it may not have moved the toe link to the aft position after all.

The 2014 Acura RLX model lineup will soon include a SH-AWD hybrid model. The spring and shock may be high up out of the way, but the rear stabilizer bar on this front-drive RLX cuts right through the middle of things and will most certainly be routed differently on the SH-AWD hybrid to make way for the drive axle.

Rear braking chores are handled by single-piston sliding calipers and 12.2-inch solid rotors.

Entry-level RLXs come with 18-inch wheels and tires, but this loaded example is fitted with Michelin Primacy MXM4 245/45R19 extra-load all-season tires on 19-by-8-inch aluminum alloy rims. Together they weigh 58.6 pounds, which isn't terribly overweight for a 19-inch factory setup of this size.
Attached Files
The following 2 users liked this post by Zoommer:
mgalbr22 (12-17-2014), Terragotti (12-30-2014)
Old 12-12-2014, 11:01 AM
  #220  
Grandpa
 
George Knighton's Avatar
 
Join Date: Dec 2003
Location: Virginia, Besieged
Age: 68
Posts: 7,596
Received 2,609 Likes on 1,475 Posts
I wonder why we have Sachs, when Honda already owns such a big chunk of Showa.
Old 12-12-2014, 11:08 AM
  #221  
Racer
 
Zoommer's Avatar
 
Join Date: Oct 2014
Posts: 287
Received 98 Likes on 52 Posts
Originally Posted by George Knighton
I wonder why we have Sachs, when Honda already owns such a big chunk of Showa.
Good question George. I actually wonder myself that same point but have no answers. I suspect that Honda made a deal with ZF to provide combo transmission/power/suspension as an integrated solution. Showa cannot do that but ZF can through its various divisions. Just a suspicion but not confirmed.
Old 12-13-2014, 07:58 PM
  #222  
Racer
 
wstr75's Avatar
 
Join Date: Aug 2006
Posts: 465
Received 189 Likes on 94 Posts
From Dan Edmunds thorough suspension review posted above:
'Others call this "double wishbone with a split lower arm." This is a mutually exclusive combination of words that I nevertheless understand completely despite knowing full well that a wishbone is a one-piece structure until after Thanksgiving dinner is finished. I found one paragraph in Acura's press kit that calls it a "double wishbone, double pivot" suspension, which makes a kind of sense if you're looking at a photograph like this one.
Whatever you call it, dual ball joints such as these improve the steering geometry by moving the lower steering pivot point outboard of where it could never hope to be if only one ball joint was present. The idea is to move the steering axis closer to the center of the tire contact patch in order to reduce the so-called "scrub radius."
Many steering-related benefits spring from this. Chief among them on front-drive machines such as this is the near elimination of torque steer, which is a good thing if your 3.5-liter direct-injected V6 makes north of 300 horsepower.'

This explains why my RLX has only the slightest hint of torque steer. I have had previous front wheel drive cars that nearly broke my wrist with torque steer. Good engineering work Honda!
The following users liked this post:
mgalbr22 (12-17-2014)
Old 12-16-2014, 09:01 AM
  #223  
Racer
 
R. White's Avatar
 
Join Date: Nov 2010
Posts: 281
Received 55 Likes on 37 Posts
I had the front suspension repair yesterday ( TSB 14-040). No more rattles. Life is good !
The following users liked this post:
mgalbr22 (01-24-2015)
Old 12-16-2014, 09:11 AM
  #224  
Instructor
 
mgalbr22's Avatar
 
Join Date: Mar 2014
Location: Cincinnati, oh
Posts: 152
Received 21 Likes on 12 Posts
Loose lumber

Originally Posted by R. White
I had the front suspension repair yesterday ( TSB 14-040). No more rattles. Life is good !
So, you never had any problem with the rear ,and the front now has no rattles and clunks?!
Old 12-16-2014, 12:30 PM
  #225  
Advanced
 
acuranj18's Avatar
 
Join Date: Jul 2013
Location: New Jersey
Posts: 90
Received 43 Likes on 26 Posts
[QUOTE=mgalbr22;15270871]So, you never had any problem with the rear ,and the front now has no rattles and clunks?![/QUOTE

Just as importantly, is there a difference in the handling, such as less bouncing on uneven roads, etc. after the changes?
Old 12-16-2014, 03:02 PM
  #226  
Racer
 
R. White's Avatar
 
Join Date: Nov 2010
Posts: 281
Received 55 Likes on 37 Posts
I never experienced any noise in the rear of the vehicle. I'll try it for a week or so in different situations to see if there is any difference in handling.
The following users liked this post:
mgalbr22 (12-17-2014)
Old 12-16-2014, 11:46 PM
  #227  
Three Wheelin'
 
holografique's Avatar
 
Join Date: Jul 2008
Location: Atlanta, GA
Age: 49
Posts: 1,793
Received 937 Likes on 487 Posts
Originally Posted by acuranj18
Just as importantly, is there a difference in the handling, such as less bouncing on uneven roads, etc. after the changes?
For me there is a slight noticeable difference in the handling. The car is somewhat less bouncy and a bit more confident in how it reacts to uneven road conditions. There is a bit of a "soft" muted response now that did not exist prior to the suspension TSB.

However, overall it is still "harsh" for this class of vehicle, and it is still not comparable to the overall suspension, ride quality, and handling of older and current vehicles in the Acura line-up, in particular the 2015 TLX. I've never driven a 1st or 2nd gen RL, so it's impossible for me to compare how it stacks up to the older RL's. But my gut says the RL is probably superior to the P-AWS RLX in general. TampaRL can probably comment more on that comparison.
The following 2 users liked this post by holografique:
acuranj18 (12-18-2014), mgalbr22 (12-17-2014)
Old 12-17-2014, 04:40 AM
  #228  
Instructor
 
mgalbr22's Avatar
 
Join Date: Mar 2014
Location: Cincinnati, oh
Posts: 152
Received 21 Likes on 12 Posts
Leverage

Originally Posted by Zoommer
Good question George. I actually wonder myself that same point but have no answers. I suspect that Honda made a deal with ZF to provide combo transmission/power/suspension as an integrated solution. Showa cannot do that but ZF can through its various divisions. Just a suspicion but not confirmed.
You are probably quite right in your assessment. For years now all of the automakers have been in the process of trying to consolidate their supply base and reduce the total number of suppliers. They have done this by sourcing systems, modules and entire chunks of the vehicle to single suppliers, which have, in turn, been driven to their own consolidation by this sourcing strategy and have made many acquisitions that offer both vertical and horizontal integration. In many cases, this process has been poorly managed as suppliers have grown too rapidly and failed to digest larger market shares. This translates into quality spills.
Old 12-17-2014, 04:57 AM
  #229  
Grandpa
 
George Knighton's Avatar
 
Join Date: Dec 2003
Location: Virginia, Besieged
Age: 68
Posts: 7,596
Received 2,609 Likes on 1,475 Posts
Originally Posted by mgalbr22
You are probably quite right in your assessment. For years now all of the automakers have been in the process of trying to consolidate their supply base and reduce the total number of suppliers. They have done this by sourcing systems, modules and entire chunks of the vehicle to single suppliers, which have, in turn, been driven to their own consolidation by this sourcing strategy and have made many acquisitions that offer both vertical and horizontal integration. In many cases, this process has been poorly managed as suppliers have grown too rapidly and failed to digest larger market shares. This translates into quality spills.
There are now only maybe four major manufacturers of dampers. It has been like that for a long time, perhaps best represented by the hilarious old fact that Showa N1, Spoon N1, and Mugen N1 suspensions all came from the same place.

They weren't exactly the same, because the native engineer could change the valving and many other things, but the same factory out them together.

In the early part of this century people argued about Skunk 2, Omnipower, and many other brands from a quality standpoint when in fact they all came from the same place. Koni is not made in the Netherlands.

😊
Old 12-18-2014, 04:03 PM
  #230  
Advanced
 
acuranj18's Avatar
 
Join Date: Jul 2013
Location: New Jersey
Posts: 90
Received 43 Likes on 26 Posts
Originally Posted by holografique
For me there is a slight noticeable difference in the handling. The car is somewhat less bouncy and a bit more confident in how it reacts to uneven road conditions. There is a bit of a "soft" muted response now that did not exist prior to the suspension TSB.

However, overall it is still "harsh" for this class of vehicle, and it is still not comparable to the overall suspension, ride quality, and handling of older and current vehicles in the Acura line-up, in particular the 2015 TLX. I've never driven a 1st or 2nd gen RL, so it's impossible for me to compare how it stacks up to the older RL's. But my gut says the RL is probably superior to the P-AWS RLX in general. TampaRL can probably comment more on that comparison.
That's kind of disappointing. I have no noise issues - just the handling issue that you accurately note.
Old 12-18-2014, 07:50 PM
  #231  
10th Gear
 
MADDOGJR's Avatar
 
Join Date: Dec 2014
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
Sounds like a possible body rattle i.e. sheet metal contact points are resonating. someone could try spraying motorcycle chain wax lube on the undercarriage sheet metal joints and then test drive. If the symptom diminishes Acura makes body shim wedges...my 2 cents
Old 12-19-2014, 06:50 AM
  #232  
Racer
 
Zoommer's Avatar
 
Join Date: Oct 2014
Posts: 287
Received 98 Likes on 52 Posts
Originally Posted by MADDOGJR
Sounds like a possible body rattle i.e. sheet metal contact points are resonating. someone could try spraying motorcycle chain wax lube on the undercarriage sheet metal joints and then test drive. If the symptom diminishes Acura makes body shim wedges...my 2 cents
Very interesting thought...the aluminum subframe and its vibration freq could be the issue. Hmmmm......
Old 12-19-2014, 01:20 PM
  #233  
10th Gear
 
MADDOGJR's Avatar
 
Join Date: Dec 2014
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
I had this same problem on my 2012 TSX SE part number billed on my RO was 07AAD-TL2A140. Not sure if it crosses over to the RLX but it fixed my problem. good luck
Old 12-21-2014, 08:58 AM
  #234  
Racer
 
Zoommer's Avatar
 
Join Date: Oct 2014
Posts: 287
Received 98 Likes on 52 Posts
Originally Posted by R. White
I had the front suspension repair yesterday ( TSB 14-040). No more rattles. Life is good !
By any chance did you ask to see the old and new parts? If so, did the parts look different or the same?

More generally-if someone is having this repair done can you take or ask the mechanic to show you old parts and take out the new parts before install and take photos of both? Would be good to post.
Old 12-21-2014, 09:02 AM
  #235  
Racer
 
Zoommer's Avatar
 
Join Date: Oct 2014
Posts: 287
Received 98 Likes on 52 Posts
Originally Posted by George Knighton
There are now only maybe four major manufacturers of dampers. It has been like that for a long time, perhaps best represented by the hilarious old fact that Showa N1, Spoon N1, and Mugen N1 suspensions all came from the same place.

They weren't exactly the same, because the native engineer could change the valving and many other things, but the same factory out them together.

In the early part of this century people argued about Skunk 2, Omnipower, and many other brands from a quality standpoint when in fact they all came from the same place. Koni is not made in the Netherlands.

😊
I would be interested in seeing what MUGEN has done with the adjustable shocks/dampers they are offering for the JDM Legend/Hybrid. Maybe that is the way to go for all of us who would like to tweak the RLX Hybrid and improve on the existing/perceived ride quality and existing issues with SACHS dampers. I thought I saw a post of someone already offering the MUGEN accessories in the US.

Who is the first person to be brave enough to take that on?
Old 12-21-2014, 09:32 AM
  #236  
Grandpa
 
George Knighton's Avatar
 
Join Date: Dec 2003
Location: Virginia, Besieged
Age: 68
Posts: 7,596
Received 2,609 Likes on 1,475 Posts
Originally Posted by Zoommer
I thought I saw a post of someone already offering the MUGEN accessories in the US.
I don't think that most of the Mugen parts will be available until later, still maybe a month or even two months away.

King Motorsports, the distributor, lists some of the Mugen parts already. Last time I looked at his site, I only saw the body parts, however. I didn't see suspension parts.
Old 12-21-2014, 09:37 AM
  #237  
Grandpa
 
George Knighton's Avatar
 
Join Date: Dec 2003
Location: Virginia, Besieged
Age: 68
Posts: 7,596
Received 2,609 Likes on 1,475 Posts
Yeah, he's only got two body parts so far, and I wouldn't count on quick delivery, either.

:-)

http://kingmotorsports.com/p-5248-mu...r-spoiler.aspx

Mugen RLX Carbon Fiber Rear Spoiler 84112-XMT-K0S0 - King Motorsports Unlimited, Inc.
Old 12-21-2014, 09:38 AM
  #238  
Grandpa
 
George Knighton's Avatar
 
Join Date: Dec 2003
Location: Virginia, Besieged
Age: 68
Posts: 7,596
Received 2,609 Likes on 1,475 Posts
Yeah, he's only got two body parts so far, and I wouldn't count on quick delivery, either.

:-)

Mugen RLX Carbon Fiber Front Under Spoiler 71110-XMT-K0S0 - King Motorsports Unlimited, Inc.

Mugen RLX Carbon Fiber Rear Spoiler 84112-XMT-K0S0 - King Motorsports Unlimited, Inc.
Old 12-22-2014, 01:28 AM
  #239  
2G TLX-S
 
Edward'TLS's Avatar
 
Join Date: Dec 2000
Location: YVR
Posts: 10,172
Received 1,133 Likes on 813 Posts
^^^^^

$2,400 for a piece of flat carbon fiber strip under the front bumper, and $1,800 for a smallish strip of trunk lid spoiler, are considered very expensive.
Old 12-24-2014, 12:39 PM
  #240  
Racer
 
R. White's Avatar
 
Join Date: Nov 2010
Posts: 281
Received 55 Likes on 37 Posts
After driving on all the crappy, frost-heaved secondary roads around here for a week after the TSB 14-040 surgery, I can report that the suspension rattling is gone.

The remaining ride issue which some have referred to as harsh is probably related to the low-profile 19" wheels. I must add that I prefer the ride of the RLX to our '13 TL which I feel is too firm.

I haven't noticed any change in handling, but I never thought that was a problem.
The following 2 users liked this post by R. White:
neuronbob (12-24-2014), wstr75 (12-25-2014)


Quick Reply: Suspension Rattle Anyone? - RLX



All times are GMT -5. The time now is 07:04 PM.