Suspension - Test Drove 2009 and 2010 Genesis back to back

[GripperDon]

Gripper Don, suggest you try the cheap things first - concentrating on rear sway bar. It is very unlikely that any aftermarket outfit will produce a sway bar narrower than the oem 17.5 mm. Consider removing the rear sway bar altogether. You'd need to have the car on jack stands with the wheels removed as most sway bars require a lateral movement for removal and wheels are in the way.
You have the V6 which is far lighter in the front than the V8 with inherently less understeer. Removing the rear bar altogether will increase your understeer, but for normal driving you will be o.k. There are plenty of vehicles out there that do not have rear sway bars. For instance my base PT Cruiser did not have a rear sway bar, but the Touring Edition does. The nice thing about rear sway bar removal is that it is easily restored. While it is out examine the bushings to determine if you have the "oval bushings."

I had read your suggestion when to posted about it some days ago and I do plan to test it just as soon as I can. It's going to be 75F again today and still have some pressing lawn sprinkler problems that are eating me up. But I plan on getting the car up on a lift and doing some more test things just as soon as I can. I keep you advised, My list of actions is mostly a result of some things I have done and other I am comtemplating. I am getting to be a bouncyness expert so I thoughts for Mike come from experience plus thinking and yours should have been added to the list. Sorry I forgot.

 

[Rey]

Did a little more research on rear sway bar diameters. According to the Hyundai mfg site the front bars' diameter for the V8 and V6 are 25 mm - both share the same bar.
They say the diameter of rear bar for the V8 is 18 mm and 17 mm for the V6.
My own measurement of my V8 rear bar (late May '09 build date) is 17.5 mm

 

[realpix]

Well I guess I'll have to say something about all this. No caps no colors no threats.

I absolutely love the car except it's ride. I am interested in discussing anything that will assist in finding ways to determine if someone has a "harsh ride" as I feel I do and ways to go about mitigating it.

Peace to all. Gripper

Well, we'll get together sooner or later and I'll let you take my 2010 V-8 for some extended driving so you can compare both your car and mine.

Short dealer drives really don't let you get the full experience....

 

[GripperDon]

How true.

 

[riverat26]

MODERATOR HAT: ON

OK kids...enough is ENOUGH

If you have issues with other members...by all means...do us ALL a favor and settle it with private messages.

This is just silly and immature.


MODERATOR HAT: OFF

Personally, if you have sold your Genesis because of a "harsh ride" what exactly is your point for being here? To TROLL around???

On behalf of Genesisowners.Com, we deeply regret that you did not enjoy your world class vehicle. However, even though you did not, there are PLENTY of us that do! I know that to some of you who sold your car that this may have caused a financial loss, others may not have, but please take your frustrations out on Hyundai...not members here at Genesisowners.com.

Yes, this forum is open to the public and any one who wants to post can do so. However, the moderators of this forum have vowed to keep this place clean and free of trash, spam, bad language, heavy sexual references, defamation of character, and the list goes on. Do we get paid for this...HECK no! We do it because we are enthusiast and we love our Genny's!

I firmly believe that the suspension issues...or lack there of...on the 09 Genny's have been beat to death...and yet for some reason...it just goes on...and on....and on. Mostly by the same people who's names you will find littered throughout the forum. Trust me, we ALL know who you are! Yes, you can continue to post all you want...but when my inbox becomes littered with reported posts about certain individuals and their posts...I tend to get a little heated up. Is that wrong of me?

Yes, the 2010 suspension is different...good or bad...that is up to each individual. Am I biased that my 09 suspension rides just fine to me...no. Hyundai admitted to the problem...and supposedly fixed it...so that says that their may very well have been an issue with the 09's.

From this point forward, if any of you (you know who you are) continue to trash talk than I will find myself hitting the infraction button. 3 clicks and your gone. Your IP address will be blocked from this site.

I would hate to do this to anyone...except spammers, because I believe we all want to tell our stories and share some wisdom...but some of us take it waaay to far in order to "one up" ourselves.

I am a life-loving, super-easy guy to get along with and I detest having to write things like this. I will be 30 years old in July...heck...IM STILL A KID and yet Im talking to adults like they are children.

From this point forward, if you have an issue with somebody's post...REPORT IT and let us deal with it...rather the typing off the cuff and stirring the pot. Please do this for us!

I love this site and I love our members and I LOVE my car! I want nothing but the best for genesisowners.com! Which means that I will take out the trash when need be!

God bless all of you and have a great day!

Matt

your absolutely right! the people that are looking into buying a genesis come to this site for good information, not to read squabbles between posters. keep up the good work! this is the most informative site on the genesis to date, and i will definately use what i have learned from the people on this site to make a wise choice! thanx again.

 

[GripperDon]

Squabbles between person indicates personal attacks and negative phraseology about another s comments. These are not useful and deter useful posts by creating a negative environment. Technical and personal observations even differing are precisely what visitors need to make informed buying and selection decisions and Hyundai requires IF they want to fix concerns of future and past buyers.

 

[Sayantsi]

I think the biggest issue is framing the design of the car as flawed because it doesn't meet personal expectations. If a person doesn't like the way the Genesis rides, there are easy and relatively inexpensive ways to remediate that. The problem arises when people claim that the car is "wrong", and thus the debate because people feel strongly that the car is great and rides fine or not.

If I loved everything about the Genesis but its firm suspension, I would go to a local suspension shop, pull a rear and front spring, have them dynoed, have a new spring made that is 30% softer or so, and have them installed on the car. $2000 fix, versus $20,000 to buy a Lexus LS with an adjustable suspension.

I have no problem with people saying that they don't like the way the car rides, but take issue when they say the car is broken and that Hyundai needs to fix something.

 

[Aquineas]

Hi folks, I'm a potential 2010 4.6 Genesis owner here (currently Acura TL owner). I have spent several hours yesterday evening reading and catching up on the issues as best I can. Thanks to all who've posted the info they have, even the frustration is good input.

I've seen some folks wondering about the SACHS ASD, and coming at this from a clean-slate perspective, this seems like it's something to look at.

Has anyone replaced their shocks with something aftermarket?

 

[Sayantsi]

Hi folks, I'm a potential 2010 4.6 Genesis owner here (currently Acura TL owner). I have spent several hours yesterday evening reading and catching up on the issues as best I can. Thanks to all who've posted the info they have, even the frustration is good input.

I've seen some folks wondering about the SACHS ASD, and coming at this from a clean-slate perspective, this seems like it's something to look at.

Has anyone replaced their shocks with something aftermarket?

I was like you when looking to buy - joined this site, started reading, read the alarmist posts about the suspension, so when I went to test drive the car, took a critical view of the suspension. I ended up driving four Genesis sedans, both V6 and V8s, on 30 minute to one hour drives, over all road surfaces. I even drove a '10 V6 model when it came out to compare, and the cars all ride the same to me. Fwiw, I autocross some of my other cars, they have had different suspensions over the years, and I know how to "read" a suspension critically, and how a suspension can drastically change a car's personality.

My conclusion is that the car rides firm - its obviously too firm for some people, but I don't think its as bad as people make it out to be. I, and many others, like the ride characteristics.

For all the solutions people have sought, I have yet to see someone go with the most straightforward solution and just have softer springs made. i don't think shocks are the big issue - you really need to drive the car yourself and see how it fits with your personal perspective if you like it or not.

 

[Bear]

I think the biggest issue is framing the design of the car as flawed because it doesn't meet personal expectations. If a person doesn't like the way the Genesis rides, there are easy and relatively inexpensive ways to remediate that. The problem arises when people claim that the car is "wrong", and thus the debate because people feel strongly that the car is great and rides fine or not.

If I loved everything about the Genesis but its firm suspension, I would go to a local suspension shop, pull a rear and front spring, have them dynoed, have a new spring made that is 30% softer or so, and have them installed on the car. $2000 fix, versus $20,000 to buy a Lexus LS with an adjustable suspension.

I have no problem with people saying that they don't like the way the car rides, but take issue when they say the car is broken and that Hyundai needs to fix something.

What are the easy and relatively inexpensive ways? A firm suspension does not have to produce a jarring ride. My mfg date is August 2008.

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[Mark_888]

What are the easy and relatively inexpensive ways? A firm suspension does not have to produce a jarring ride. My mfg date is August 2008.

According to HMA employees who posted on the Hyundai Think Tank website, Hyundai modified the 2010 suspension (some say it was actually modified mid-2009) by "changing the spring and shock rates." The general consensus is that the rear springs were overpowering the shocks, so the adjustment was to soften the springs and beef up the shocks on the rear. The adjustments were minor and the ride is still firm, but with less bounciness and better control on the rear.

Personally, I think it should be possible for an experienced independent suspension shop to order the 2010 OEM rear springs and shocks and put them on the 2009. But if you are looking for a much softer ride, then that is a different story. Maybe someone can figure out how to import and install the air shocks that come on the Korean version of the Genesis (which HMA decided was too soft for the American automotive press).

 

[Disaster]

My conclusion is that the car rides firm - its obviously too firm for some people, but I don't think its as bad as people make it out to be. I, and many others, like the ride characteristics.

For all the solutions people have sought, I have yet to see someone go with the most straightforward solution and just have softer springs made. i don't think shocks are the big issue - you really need to drive the car yourself and see how it fits with your personal perspective if you like it or not.

I've got some experience racing and tuning suspensions as well...including working for an automotive company. Without, the correct equipment, it is difficult to optimize the suspension or know exactly how to do that, but a general evaluation can be made by examining how it reacts to small and large inputs...fast and slow. The suspension engineers can tune the shock for fast and slow inputs and for compression and rebound damping.

I've noticed, while firm, the suspension handles quick small or large inputs, fairly well... albeit firmly. It also handles well statically...say when going around a large sweeping turn...like an on ramp. However, when the inputs are spaced further apart I notice the suspension hasn't damped the first input by the time it gets the second one. The car pitches more than it should on some roads (compared to other cars with similarly firm suspensions.) Some people have experienced this pitching on highways with equally spaced undulations, and have likened it to porpoising...with the car pitching forward and backward. This suggests there is a lower frequency that isn't being damped properly...and the suspension is hitting resonance.

Any spring and mass has a resonance...actual several (and 1st order, 2nd order...etc.), where inputs at a frequency will cause greater and greater amplitude.
http://hyperphysics.phy-astr.gsu.edu/hbase/shm2.html

http://en.wikipedia.org/wiki/Harmonic_oscillator

http://en.wikipedia.org/wiki/Vibration

This can happen if the slow damping is insufficient...or if there is not enough rebound damping in general. Lightening the springs will help with the stiffness, but might actually move the resonance into a worse range. The Genesis might be better served with tuning both...the spring rate and the damping.

http://www.ast-usa.com/resources/Critical-Damping.pdf

http://www.shock-shop.com/Thoughts%20on%20Damping/Shock%20Tuning.htm

From this source. http://shimrestackor.com/Physics/Spring_Mass_Damper/spring_mass_damper.htm

"Under damped suspension response zeta<1:

If the suspension is under damped (z< 1) the suspension will oscillate and baby buggy a couple of times before settling down on top of the step. While this is an intuitive result it is important to note that the equations duplicate this behavior. In addition the equations give you an exact numerical description of the process. For a damping coefficient of 0.2 (z=0.2) the suspension will overshoot the 10" bump by about 5", then undershoot by 3" and baby buggy a couple more times before setting down on top of the step. All of this motion occurs within 1.2 seconds of hitting the bump. As the value of the damping coefficient (z) increases the overshoot decreases as well as the number of baby buggy oscillations and the time required to damp the system."

http://www.se-r.net/suspension/shock_tech.html

"Today, street performance shocks have rebound damping rates that are two or more times greater than compression damping rates. The single action of adjusting bleed to affect bump and rebound is, by definition, a 50/50-style change, so the overall damping proportion will change as more bleed is dialed in. Independent adjustments allow the alteration of one characteristic while not affecting the other; this is therefore more precision and involves less compromise."

http://en.lfsmanual.net/wiki/Advanced_Setup_Guide
" The critical damping is the strength of the rebound damping needed to stop suspension movement the quickest after motion has started."

If it bothers me enough, I may pick up some adjustable coil overs....though this is an expensive option. Getting someone to fab springs isn't too hard, but it is also expensive, and often a trial and error process...which makes it even more expensive. Before I went out and bought the 2010 spring and struts I'd want to know how much of a difference they made.

 

[doug725]

I would just like to reiterate that, indeed, most of the cars ride fine and many people are satisfied with the ride as you are. I wish I had been one of them as do many others. Again, the demo I test drove extensively was OK. However, it is a fact that some of the vehicles do/did indeed have a problem and exhibit more extreme behavior as mine and a couple of others I later drove did. It is not a preference issue - it is downright odd behavior for any vehicle that is the point in question. The issue keeps surfacing. Most people are not bringing it up and going to these extremes to find a remedy simply because they are finding their ride just a bit too firm for their taste.

I recently test drove a 2010 and found it a bit more composed - much more like the demo I originally drove over a year ago.

I was like you when looking to buy - joined this site, started reading, read the alarmist posts about the suspension, so when I went to test drive the car, took a critical view of the suspension. I ended up driving four Genesis sedans, both V6 and V8s, on 30 minute to one hour drives, over all road surfaces. I even drove a '10 V6 model when it came out to compare, and the cars all ride the same to me. Fwiw, I autocross some of my other cars, they have had different suspensions over the years, and I know how to "read" a suspension critically, and how a suspension can drastically change a car's personality.

My conclusion is that the car rides firm - its obviously too firm for some people, but I don't think its as bad as people make it out to be. I, and many others, like the ride characteristics.

For all the solutions people have sought, I have yet to see someone go with the most straightforward solution and just have softer springs made. i don't think shocks are the big issue - you really need to drive the car yourself and see how it fits with your personal perspective if you like it or not.

 

[Seattle Genesis]

I've got some experience racing and tuning suspensions as well...including working for an automotive company. Without, the correct equipment, it is difficult to optimize the suspension or know exactly how to do that, but a general evaluation can be made by examining how it reacts to small and large inputs...fast and slow. The suspension engineers can tune the shock for fast and slow inputs and for compression and rebound damping.

I've noticed, while firm, the suspension handles quick small or large inputs, fairly well... albeit firmly. It also handles well statically...say when going around a large sweeping turn...like an on ramp. However, when the inputs are spaced further apart I notice the suspension hasn't damped the first input by the time it gets the second one. The car pitches more than it should on some roads (compared to other cars with similarly firm suspensions.) Some people have experienced this pitching on highways with equally spaced undulations, and have likened it to porpoising...with the car pitching forward and backward. This suggests there is a lower frequency that isn't being damped properly...and the suspension is hitting resonance.

Any spring and mass has a resonance...actual several, where inputs at a frequency will cause greater and greater amplitude.
http://hyperphysics.phy-astr.gsu.edu/hbase/shm2.html

http://en.wikipedia.org/wiki/Vibration

This can happen if the slow damping is insufficient...or if there is not enough rebound damping in general. Lightening the springs will help with the stiffness, but might actually move the resonance into a worse range. The Genesis might be better served with tuning both...the spring rate and the damping.

If it bothers me enough, I may pick up some adjustable coil overs....though this is an expensive option. Getting someone to fab springs isn't too hard, but it is also expensive, and often a trial and error process...which makes it even more expensive. Before I went out and bought the 2010 spring and struts I'd want to know how much of a difference they made.

Tomorrow I will be visiting an auto suspension expert here in Seattle for them to examine and recommend a better spring. Hopefuly they will feel the same issues as I do. I will keep yall posted on what the diagnosis and cure is, if any.
Seattle Genesis

 

[GripperDon]

Lower spring rate front and rear, greater inital free length. set so thst the loaded height is the same as current value ( saves re-alignment) reduce dompression dampening and increase rebound loading.

 

[thomaspf]

Hi SeattleGenesis,

let me know what you find. I am Seattle as well and might join you if that helps convincing the shop to do the work.

Cheers

Thomas