I've been sitting on the photos of the 2009 Hyundai Genesis V6 sedan suspension walkaround for a week because I wanted to put them up about the same time as those of a 2009 Hyundai Genesis Coupe V6.
From the name similarity, some might figure that the two share a chassis. But that assumption turns out to be bogus. There are some humungous differences within these fenders.
About all I can conclude from this exercise is this: The common thread that links the two Genesis products in the Hyundai lineup is rear-wheel drive.
The front suspension of our Genesis sedan could not be more different from that of a Genesis Coupe.
First, it's nothing close to a MacPherson strut setup. It looks like a double wishbone layout with an elongated knuckle (white) leading to a high-mount upper arm and a coil-over shock (black).
But there aren't any upper and lower wishbones because dual links with separate ball joints are used top (yellow) and bottom (green). Some people might call this a 4-link suspension, while others will include the steering tie-road and call it 5-link. But I find that nomenclature too generic without pictures to back it up.
If that wasn't enough, most of what you see here is made from aluminum. You can afford to make those sorts of upgrades when the price tag is $10k higher than your sibling's.
Imagine where these dual upper links would intersect in space if they were projected out and you'll find the location of the virtual steering axis. Yeah, that's right; about 1.5 inches out from your computer screen.
The same thing is going on at the bottom, too. It looks more like the Genesis Coupe down here, except everything is made of aluminum.
Here we can see how the short link from the front stabilizer bar (white) connects to a bracket (black) on the lower end of the coil-over housing. This means they both share the same motion ratio with respect to the lower link. I call it 0.65 or thereabouts.
The major steering and suspension components are all carried by the front subframe, Direct-mounting it to the chassis (white) is a move intended to foster good steering precision.
The front brakes are single-piston (white) sliding calipers and one-piece ventilated rotors (black) -- a tried-and-true setup that works well in cases where track use isn't in the cards.
Note the dual Hyundai and Kia logos molded into the casting.
The rear suspension of the Genesis sedan looks a lot more similar to that of the Genesis Coupe. That said, there are differences that make it likely that none of the parts are interchangeable.
Here you can see that the sedan employs a multilink suspension with 5 links -- just like the coupe. Two upper links (white) and two lower links (black) locate the wheel and describe the caster and camber. The 5th unseen link, a toe link, keeps the tire pointed straight ahead.
This view looks similar to that of the coupe, but with one exception: the rear suspension knuckle (yellow) is made of aluminum, not steel.
Here we're looking back (and up) at the rear suspension, looking at the same pair of lower links (black) and upper links (white). But now we can see the toe link (yellow) and see that it is much shorter than the other links to produce a bit of stabilizing toe-in during hard cornering and emergency maneuvers.
Now we're looking from behind, and this is where some of the more visible differences from the Genesis Coupe can be found.
For one, the stabilizer bar attachment point is very close to the hub, creating a motion ratio somewhere north of 0.8. The stabilzer bar (green) can therefore generate a decent amount of roll stiffness, despite appearing far smaller than the one in the coupe. Is it generating as much roll stiffness as the Coupe? Probably not. But the difference isn't as big as your eyes tell you it is because of the different mounting strategies. (See here for the Genesis Coupe walkaround.)
Another big difference is the rear shock mounting point (white), barely visible here. It bolts directly to the hub for maximum damping efficiency. You don't need the shock to produce overly-high forces if you can make use of all it has to offer with a 1:1 motion ratio such as this.
Here's a better shot of the shock absorber (green) and it's direct-mount to the rear knuckle.
We haven't seen a bump stop yet, which means it's more than likely hidden within the dust boot at the top end of the shock absorber.
Like the front, the Genesis sedan uses single-piston sliding calipers (white) on the rear axle. Unlike the front, the rear rotors (yellow) are solid non-ventilated discs.
Our Genesis V6 sedan rides on Dunlop SP Sport 5000M all-season tires, sized P235/50R18. Together with their 7.5 x 18-inch rims, each weighs 50.5 lbs on my garage scale.
Dan Edmunds, Director of Vehicle Testing @ 15,654 miles
texases says:
04:00 PM, 09/ 2/09
Dan, these just get better and better. Now you're giving us a good understanding of how the "Genesis" name is only skin deep. Great stuff!
tjpark01 says:
04:15 PM, 09/ 2/09
Thank you! The car is stiff, but it's a good stiff. More Infinit/BMW, and less Lexus/MB. I have a V8, aside from the brakes (4 piston on the V8), I think the suspension and tire set up is the same. Munimula all the way!!!
cruiserhead1 says:
05:03 PM, 09/ 2/09
I think the confusion about the Genesis name comes from the plan Hyundai cut short.
Originally, Genesis was a brand name (like Lexus).
Hyundai dealers balked at setting up a Genesis dealership so this is what we have. That is also why they don't have the Genesis wings emblem in the USA. That would be like putting a Toyota and Lexus emblem on the same car.
dg0472 says:
06:10 PM, 09/ 2/09
This would probably be a good place to note that Hyundai issued a press release this week promising revised suspension and steering for the 2010. No specifics on what those changes are. Also new of note: touch screen nav.
See here:
http://www.hyundainews.com/Media_Kits/2010_Models/Genesis/Press_Release.asp
cwc1 says:
07:10 PM, 09/ 2/09
Interesting about the Genesis originally being planned as a "brand". Sounds a bit like the Amati network that Mazda was going to set up in the '90s, which got canceled because Mazda decided it would be too expensive.
Revised suspension in 2010, already? I wonder why, since the Genesis vehicles came out just this year, and from what I've read, their ride and handling are quite good.
cx7lover says:
08:32 PM, 09/ 2/09
Hyundai calls it a Multilink/5 so that's what it is.
cx7lover says:
08:32 PM, 09/ 2/09
http://www.sae.org/technical/papers/2009-01-0224
dg0472 says:
08:38 PM, 09/ 2/09
I've heard many comments that on some sharp or larger bumps it can get a bit "unsettled".
bradyholt says:
08:41 PM, 09/ 2/09
There have been some complaints about the car's ride quality on certain types of pavement, so hopefully this addresses this.
Of course, when Hyundai says in its press release "we improved ride and handling", one has to wonder "why didn't you do this the first time?"
dg0472 says:
08:45 PM, 09/ 2/09
I guess they're responding to customer complaints. The '08 and '09 Azera releases both claim suspension revisions, so I guess they're doing fine-tuning, seeing what the market says, and trying again if they're still getting complaints.
actualsize says:
09:41 PM, 09/ 2/09
I think I'd give Hyundai a pass on the "Why didn't they do it right the first time?" question. Why would I say that?
Well, Hyundai is moving into virgin territory with the Genesis sedan -- far upmarket from where they've been before. As such, there was no history or track record established for a luxury Hyundai. Would it attract those who prefer Lexus' soft ride or would they gain sales from those who prefer the firmness of a German marque? Will they attract Cadillac owners? Customer surveys and focus groups can only tell you so much about how folks might react to a rear-drive V8 Hyundai sedan they've never dreamed of before.
With that in mind, the basic character of the car is quite good. The ride is neither too mushy nor too brittle. There's a lot of fundamental goodness here.
That said, the rear suspension tuning could stand a little tweaking. The four of us (450 lbs total; 350 in front, 150 in back) ran errands around town in this V6 and I came away with a feeling that the rear was getting into the bump stops a little too early. I'm not saying it was bottoming out -- it wasn't. But it felt like a long, progressive bump stop is hidden inside those shocks, and the engagement point was a little too obvious in a way that restricted the smooth stroking of the rear suspension. If this happened in a corner, then I could see how the term "unstettled" might apply in certain circumstances.
ampim says:
05:51 AM, 09/ 3/09
Nice walk around, but the sedan's suspension (front especially) looks like tech for tech's sake. True, having two-link control arms allows you to move the effective ball joint out to a a place where it couldn't exist physically, but is that really necessary? Why then is BMW moving back to simple MacPherson setups (and why has Porsche done this all along)? All those extra links and ball joints add mass and cost. Perhaps marketing bragging rights?
In the end, it all comes down to the tuning. You need to have a suspension design in place that gives the engineers just enough knobs to turn. To many knobs, too many costs. Although I have a morbid curiosity to see how BMW would tune a live axle suspension.
prndlol says:
06:22 AM, 09/ 3/09
I actually get a lttle giddy when i discover one of these excellently presented suspension walkaround entries. Tremendous work, Dan.
prndlol says:
06:58 AM, 09/ 3/09
I actually get a lttle giddy when i discover one of these excellently presented suspension walkaround entries. Tremendous work, Dan.
prndlol says:
07:00 AM, 09/ 3/09
Whoops i came back and refreshed the page a half hour later and it resubmitted my comment LOL
jeffal says:
09:16 AM, 09/ 3/09
I am actually surprised (in a good way) that Hyundai is reacting so quickly to the enormous amount of criticism regarding the suspension on the Genesis.
Complaints from owners on other Genesis message boards is growing and growing. Not to mention car magazine reviews citing the suspension and ride over bumpy roads as a Genesis weakness.
I would have thought Hyundai would wait until the 2011 or 2012 model year to make changes to the suspension, but the fact that they are reacting so quickly and making the changes to the 2010 is very promising for the company. I might actually get one for myself.....I just wish they would add fold-down rear seats as an option.
jyym says:
09:55 AM, 09/ 3/09
Interesting enough, the Acura TSX and the BMW 135i also have had complaints about the ride being unsettled on less smooth pavement.
It'll be interesting to see how quick Acura and BMW react to such complaints and make some adjustments to their suspension tuning (it took a while before BMW made an improvement to the suspension of the X3, and it wasn't quite enough of an improvement for many).
whs says:
06:10 AM, 09/ 5/09
Dan,
Thanks for the education. Your techinical descriptions are really interesting(the how and why the engineering works). Keep up the great techinical writings.
yellowmiata says:
06:29 AM, 09/ 9/09
Dan,
This is a wonderful writeup and walkaround. I really enjoy seeing and reading about the specific parts as well as your bits about why the manufacturers may have placed a piece here or there. Suspension geometry is something I know little about and these are a good beginning to my education. Thank you!
Kevin
conceptvbs says:
02:22 PM, 09/ 9/09
@ jeffal
Hyundai did mention that fold down rear seats will be available in future models. However, they did not specify when.
gripperdon1 says:
11:09 PM, 09/20/11
Great bunch of pictures, However my Genesis is the harshest riding car I have ever owned or riden in. I am hopeing to fis Air bags to it.