No KDSS for FJ Cruiser ?

[Thai]

harper...really dude? Love you like a brother, but your arrogance is laughable.

Koolaid? Did you even bother to read the ACTUAL RTI measurements b/w a GX470 with KDSS and one without? Wow.

And i see that you still hold a grudge regarding our prior arguments regarding your Android phones...sorry if i hurt your feelings...but still love you like a brother!

 

[gray street]

That's because you are clueless to the suspension mechanical parts on a 5th Gen 4Runner or how they work.
I've changed several 5th Gen suspensions with KDSS and without .I know for a FACT that they do not increase articulation as I know what the actual physical limits of the 5th Gens Independent Front Suspension and rear 4-link suspension are. How many have you worked on to get your mechanic experience or do you just drink the marketing kool aid??? I'd like to hear your opinion on what the actual up and down stops are?

There's plenty of pics and discussions on here showing the parts and how they work,not to mention the Toyota factory manual, if you want to educate yourself on the topic. http://www.toyota-4runner.org/5th-gen-t4rs/99169-where-find-kdss-parts-list.html#post878491

Stick with things you actually have experience in ,like Iphones minivans and Prius's instead of disputing something you are clueless about :biggrin2:

Still love ya man!

If one is crawling, you believe that both will flex the same?

 

[harper7]

harper...really dude? Love you like a brother, but your arrogance is laughable.

Koolaid? Did you even bother to read the ACTUAL RTI measurements b/w a GX470 with KDSS and one without? Wow.

And i see that you still hold a grudge regarding our prior arguments regarding your Android phones...sorry if i hurt your feelings...but still love you like a brother!

I never worked on or claim to know what the differences in a GX470 KDSS and non KDSS GX470 so a RTI measure of a GX470 with their air suspension is useless information.
Show me a RTI comparing 5TH gen models and you'll have something!This is a 5th Gen 4Runner sub forum and what was being discussed is a 5th Gen suspension.A subject that obviously know nothing about!

 

[1engineer]

harper...really dude? Love you like a brother, but your arrogance is laughable.

Koolaid? Did you even bother to read the ACTUAL RTI measurements b/w a GX470 with KDSS and one without? Wow.

And i see that you still hold a grudge regarding our prior arguments regarding your Android phones...sorry if i hurt your feelings...but still love you like a brother!

Thai you are wrong. Harper is right. Harper has worked on both. I am thinking of trading for a TE with KDSS and I crawled underneath a new TE on Sunday. Guess what...same geometry as my SR5. No difference as stops are same. Wouldn't you think someone like elltee who builds suspension components would know a few things too? Sorry man I enjoy your posts otherwise but all you proved here is you know how to read magazine articles. I can't explain why they got different RTI scores on a Lexus but I know what I see and know who to trust on such things.

 

[MT4X4]

I never worked on or claim to know what the differences in a GX470 KDSS and non KDSS GX470 so a RTI measure of a GX470 with their air suspension is useless information.
Show me a RTI comparing 5TH gen models and you'll have something!This is a 5th Gen 4Runner sub forum and what was being discussed is a 5th Gen suspension.A subject that obviously know nothing about!

The GX470 has the same suspension as the 5th Gen 4Runner and 2010+ FJ Cruiser which all use the Prado 150 platform.

Using the RTI score is kinda vague due to so many variables of each vehicle. You can easily drop the psi in the tires to 5lbs and gain another 100 points due to sidewall flexing. If all things equal then only thing that could give a GX470 with KDSS more "flex" is the forced compression of the sway bar otherwise the extended travel remains the same.

 

[Thai]

Thai you are wrong. Harper is right. Harper has worked on both. I am thinking of trading for a TE with KDSS and I crawled underneath a new TE on Sunday. Guess what...same geometry as my SR5. No difference as stops are same. Wouldn't you think someone like elltee who builds suspension components would know a few things too? Sorry man I enjoy your posts otherwise but all you proved here is you know how to read magazine articles. I can't explain why they got different RTI scores on a Lexus but I know what I see and know who to trust on such things.

I love how the suspension expert aka harper forgot that there isn't much difference b/w GX470 suspension and that of 5th gen 4runner!

BTW, both GX in the 4wheeler test had air suspension. So, equal ground for comparison.

Simply put, the KDSS allows better suspension travel. You don't need to be rocket scientist to understand the concept...nor do you have to be a self-proclaimed suspension expert!

Remember, we're talking about suspension flex off-road, not absolute travel without sway bars. The sway bars on SR5 and Limited are what limits the travel.

And please, don't say that 4wheeler don't know how to test RTI. :bash:

Are you saying that a Rubicon Wrangler doesn't have more suspension flex than a non-Rubicon model simply because the suspension stops are the same?????

BTW, READ what FourWheeler wrote...they notice the improved travel in REAL LIFE too, not just with RTI ramp:

"Since we liked the Lexus last year, it is no surprise that we liked it even better this year, since it has greater articulation. Sure, at first some of us thought the KDSS system was a gimmick. But then we ramped the GX and found that increased articulation was notable and, on a 20-degree ramp, provided a 519 RTI, compared to an RTI score of 428 on a GX 470 without KDSS. This increased articulation is readily apparent on the trail, where the flex of the rear suspension helps the Lexus stay planted on the ground so that it can find traction."

 

[harper7]

If one is crawling, you believe that both will flex the same?

Not following you.Yes, there is a 650in/lb or 700 in/lb spring pushing down on the wheel assembly to the UCA ball joints limit or the 2 1/2 ton weight of the truck compressing the spring and pushing the wheel up til it rest against the bump stop on the frame. What exactly do you think would be holding the non KDSS wheel from articulating less then a KDSS one.

There are actual physical stops limiting articulation.
The UCA's ball joint articulation,or the the shock if it doesn't have enough travel is the limit for down travel.period
The hard rubber bump stop on the frame where the LCA's comes up and contacts it is the limit for the up travel.period
This isn't a Jeep with a SAS front suspension with alot more travel where the sway bar limits travel.

 

[Antman]

I definitely believe everything I read in magazines, especially 4Wheeler.:nerd:

 

[gray street]

Not following you.Yes, there is a 650in/lb or 700 in/lb spring pushing down on the wheel assembly to the UCA ball joints limit or the 2 1/2 ton weight of the truck compressing the spring and pushing the wheel up til it rest against the bump stop on the frame. What exactly do you think would be holding the non KDSS wheel from articulating less then a KDSS one.

There are actual physical stops limiting articulation.
The UCA's ball joint articulation,or the the shock if it doesn't have enough travel is the limit for down travel.period
The hard rubber bump stop on the frame where the LCA's comes up and contacts it is the limit for the up travel.period
This isn't a Jeep with a SAS front suspension with alot more travel where the sway bar limits travel.

If you would check out what I posted on the third page, you might understand what I mean better.

 

[Thai]

This whole thread comes down to one thing. Do you think that sway (anti-roll) bars affect wheel articulation in off-roading if all else being equal?? This is the case according to you guys, right? SR5 and TE have exact same suspension except for sway bar diameters and KDSS.

If NO, then i have nothing else to say.

If YES, then please read on.

KDSS disconnects the sways, right? If yes, then that means that sway bars have no effect right on axle travel when KDSS is activated (at slow speed), right? The axle(s) can swing at max capacity.

With SR5, sway bars are always connected, right? Yes, they are thin sways, but they are connected nonetheless.

So, with that out of the way, which do you think has more suspension travel in a cross-axled situation...one with no sways (KDSS) or one with sways connected (SR5)??

 

[harper7]

This whole thread comes down to one thing. Do you think that sway (anti-roll) bars affect wheel articulation in off-roading if all else being equal?? This is the case according to you guys, right? SR5 and TE have exact same suspension except for sway bar diameters and KDSS.

If NO, then i have nothing else to say.

If YES, then please read on.

KDSS disconnects the sways, right? If yes, then that means that sway bars have no effect right on axle travel when KDSS is activated (at slow speed), right? The axle(s) can swing at max capacity.

With SR5, sway bars are always connected, right? Yes, they are thin sways, but they are connected nonetheless.

So, with that out of the way, which do you think has more suspension travel in a cross-axled situation...one with no sways (KDSS) or one with sways connected (SR5)??

The KDSS sway bars are connected to the LCA's and do NOT disconnect........ever!
Did you read and look at the pics on the link I provided you with the TE parts?
The SR5/LE sway bars have flexible jointed links that connect it to the spindle ,that allow the sway bar to not bind or inhibit articulation. I can show you pics of that too as this has been discussed about 20 times already.
Some of the suspensions I installed.
KDSS TE/Toytec Ultimate/TC uca's

LE/Icons remotes/TC uca's

LE/Icons/ Icon /Icon billet uca's

 

[Koz]

You don't have to be a suspension specialist to understand that if a sway bar is connected, it will be the limiting factor, not the stops. The KDSS controls that limit and allows the suspension to articulate as though there was no sway bar attached. The RTI tests verify this. Then again, I'm sure the suspension experts and engineers on this site know more then the dedicated automotive engineers for OEMs.

Koz

 

[Thai]

harper, so KDSS does not relax the axles so that it can go thru the whole motion? You're telling me that KDSS still limits the axle movement?

According to Edmunds link by Koz: (like harper i assume, Insideline crawled underneath the GX and examined the KDSS up close!)

"KDSS is a hydaulic system that's fully automatic -- there are no switches on the dash because there is no need to turn it on or off. Instead, the front and rear stabilizer bars feature hydraulic cylinders on their left-hand sides, with piping connecting the two and a valve in between.

In a corner, both cylinders are squeezed (right turns) or stretched (left turns) in the same direction. Such "in-phase" loading produces front and rear pressures that are more or less equal, which holds the valve closed to keep those cylinders absolutely rigid so the stabilizer bars can deliver their full roll-resisting effects.

But frame twist off-road conditions -- and our RTI ramp -- produce positive pressure in the cylinder that's being compressed and negative pressure in the one being stretched. Such "out-of-phase" axle articulation causes the valve to pop open, which makes the cylinders go limp and take the stabilizer bars out of the picture.

But the stabilizer bars are not cut in two; they're still one-piece hunks of bent metal. When rigid, the cylinder is merely a link holds the pivot bushing in space, much like the rear stabilizer bar setup on a Ford Mustang. But here the open valve allows the cylinder to expand and contract at will, allowing that pivot bushing to float around and prevent the stabilizer bar from generating any torque."
-----------------------------------------------------------------------------------------------------------------------------------------

So, i believe that what i wrote above is quite accurate, as backed up by Insideline (and personal experience seeing KDSS in action). KDSS does indeed "disconnect" the sways, but not in the traditional sense (like what Wrangler Rubicon and traditional off-roaders do).

According to Insideline:

"What's all this good for? Some 20.2 inches of wheel lift, almost 2 inches MORE than our unmodified 2012 Jeep Wrangler Sport 2-door managed and only a quarter-inch less than the Jeep with its big tires fitted."

What do the stock SR5s have as far as wheel lift measurements? Lets see some stock numbers!

 

[1engineer]

You don't have to be a suspension specialist to understand that if a sway bar is connected, it will be the limiting factor, not the stops. The KDSS controls that limit and allows the suspension to articulate as though there was no sway bar attached. The RTI tests verify this. Then again, I'm sure the suspension experts and engineers on this site know more then the dedicated automotive engineers for OEMs.

Koz

No I don't know more than the OE engineers about their own designs. I can assure you though I know more than advertising writers and marketing planners about engineering.


So Koz are you saying that if sway bars are connected (on 5th Gen 4Runners)that will be the physical limiting component (the sway bar) and will be the component that stops the wheel from travelling upwards or downwards thereby determining maximum articulation? This is what you alluded to in your post and Thai too.

 

[Thai]

1engineer, let me ask you an opposite question...you think that sway bars have no role in off-road articulation? No one is arguing what the max wheel travel a 4runner can achieve. You're right. Bumpstops etc. are there for a reason. HOWEVER, when traveling over uneven terrain (aka off-road), you're saying that sway bars have no effect in wheel articulation?

If so, then why do folks disconnect the sways when off-roading?

The SR5/LE sway bars have flexible jointed links that connect it to the spindle ,that allow the sway bar to not bind or inhibit articulation.

And from harper's post, it seems like sways serve no purpose...because the sways in the SR5 are useless doing its job! So, what the hell does it do??? Is it like the human appendix?!

Please read again what Insideline states after closely examining the KDSS system.

 

[1engineer]

harper, so KDSS does not relax the axles so that it can go thru the whole motion? You're telling me that KDSS still limits the axle movement?

According to Edmunds link by Koz: (like harper i assume, Insideline crawled underneath the GX and examined the KDSS up close!)

"KDSS is a hydaulic system that's fully automatic -- there are no switches on the dash because there is no need to turn it on or off. Instead, the front and rear stabilizer bars feature hydraulic cylinders on their left-hand sides, with piping connecting the two and a valve in between.

In a corner, both cylinders are squeezed (right turns) or stretched (left turns) in the same direction. Such "in-phase" loading produces front and rear pressures that are more or less equal, which holds the valve closed to keep those cylinders absolutely rigid so the stabilizer bars can deliver their full roll-resisting effects.

But frame twist off-road conditions -- and our RTI ramp -- produce positive pressure in the cylinder that's being compressed and negative pressure in the one being stretched. Such "out-of-phase" axle articulation causes the valve to pop open, which makes the cylinders go limp and take the stabilizer bars out of the picture.

But the stabilizer bars are not cut in two; they're still one-piece hunks of bent metal. When rigid, the cylinder is merely a link holds the pivot bushing in space, much like the rear stabilizer bar setup on a Ford Mustang. But here the open valve allows the cylinder to expand and contract at will, allowing that pivot bushing to float around and prevent the stabilizer bar from generating any torque."
-----------------------------------------------------------------------------------------------------------------------------------------

So, i believe that what i wrote above is quite accurate, as backed up by Insideline (and personal experience seeing KDSS in action). KDSS does indeed "disconnect" the sways, but not in the traditional sense (like what Wrangler Rubicon and traditional off-roaders do).

According to Insideline:

"What's all this good for? Some 20.2 inches of wheel lift, almost 2 inches MORE than our unmodified 2012 Jeep Wrangler Sport 2-door managed and only a quarter-inch less than the Jeep with its big tires fitted."

What do the stock SR5s have as far as wheel lift measurements? Lets see some stock numbers!

So do you want to go back and recant your original assertion that a 5th Gen 4Runner with KDSS physically disconnects the sway bar? It just moves the pivot point and makes them inefffective. I posted that myself in an earlier response. So I will ask you the same question as Koz: Do you think, that on a 5th gen 4Runner (no Jeeps or air ride Lexus because that is what this thread is about lol) the sway bar being connected (SR5) vs the act of rendering it ineffective by moving the pivot (KDSS equipped Trail Edition) is the component that will physically limit the upward and downward travel of the wheel? This is suspension articulation>

 

[Thai]

So do you want to go back and recant your original assertion that a 5th Gen 4Runner with KDSS physically disconnects the sway bar? It just moves the pivot point and makes them inefffective.

Why would i? KDSS makes sways INEFFECTIVE, right? What does that mean? You tell me. How different is that from what i wrote? Come on dude!

BTW, since both GX470 had air bags, doesn't that take that out of the equation?? You're a math expert...you tell me.

 

[1engineer]

1engineer, let me ask you an opposite question...you think that sway bars have no role in off-road articulation? No one is arguing what the max wheel travel a 4runner can achieve. You're right. Bumpstops etc. are there for a reason. HOWEVER, when traveling over uneven terrain (aka off-road), you're saying that sway bars have no effect in wheel articulation?

If so, then why do folks disconnect the sways when off-roading?



And from harper's post, it seems like sways serve no purpose...because the sways in the SR5 are useless doing its job! So, what the hell does it do??? Is it like the human appendix?!

Please read again what Insideline states after closely examining the KDSS system.

Sorry Thai apparently we were posting at the same time! I think some are getting confused with terminology. You guys were using RTI scores and magazine articles to try to make a point that KDSS somehow magically adds extra inches to maximum wheel travel on IFS 5th Gen 4Runners. If you have a SAS front that changes things. No it does not. Now, that is one issue and you are right to agree bumpstops control that and they are located in the same place for all models of 4Runners. The above is only concerning articulation and it's limits.
On KDSS equipped 4Runners:
What having a KDSS 4Runner WILL give you off road is improved suspension response time. How much? I don't know. Let's assume an example:
Let's say you are travelling on a rough fire road at 20 mph with lots of ruts and small rocks. In a non KDSS equipped 4Runner you only have gravity and spring force (both coils and sway torsion) to keep the wheels in contact with the dirt. On KDSS equipped 4Runners you will have gravity and hydraulic pressure to keep the wheels in contact with the surface. I'm sure it's faster on the KDSS and allows less "bounce" resulting in a better ride over the rough stuff.
Now back to articulation:
Knowing now what I just told you above let's think of another scenario:
You are going down this fire road and you get to a 1 foot rock ledge that is across half the trail. The KDSS equipped 4Runner, while not giving you any more articulation than a non KDSS 4Runner will allow the wheels to travel up or down EASIER because of reasons listed above but only until the limits of the stops, which are the same for both vehicles.

So, to conclude, will you get more articulation from a KDSS 4Runner with IFS than a non KDSS 4Runner? No. Both min-max's are the same. Will it give you a better ride (both on and off road) and possibly (depending on the terrain) keep the tires planted better and allow easier up-down movement of the wheels on the tougher stuff? Yes it could.

 

[NorthWest 4R]

You can keep you're damn KDSS :bash: :rockthrow:

:jk:

The KDSS on the TE is why I went with the limited in the end. I wanted all the options that does not come on the SR5, but will be easier to scrap the OEM suspension in the long run. I don't know what all would be involved with removing the KDSS system, or if it would then throw a code or not. I will be going full long travel with the 4R, so I will have no sway-bars period and didn't want to hagle removing the KDSS system.

Yes KDSS is nice, but so is the XREAS (for the street ). It all depends on what you are using you're 4R for and different systems will shine in better areas than others in certain circumstances. KDSS is just the stability of the XREAS in the city, but more tailored towards going offroad as well. But then compare a KDSS equipped 4R with just some off the shelf coilovers to a full LT kit with secondary's, bypasses, bump cans and you will really see the light :bigok:

 

[mgrande]

I'll bet good money that no one can produce pictures of a TE 4runner with one front wheel at full stuff and the other completely maxed out. Ain't gonna happen, any sway bar will limit articulation.