E-KDSS

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Our friend Kai He from Tinkerer Adventure try to do a deep dive on EKDSS.


He and I think a lot alike. I don't always agree with some of his analysis, but I think he does a great job on his videos. Far better than most!

In the video he discusses the articulation spec vs real world and the differences. My bet is that Toyota's number is based on a calculated max that includes the compression of the bump stops as what they consider fully articulated and in the real world at slow speeds or no speed you wouldn't actually be compressing through the bump stops or possibly even touching the bump stops. So there's more up travel in the suspension and flex in the rubber bushings than is used during a low speed mogul or static measurement. That probably accounts for the difference in the two measurements.

I thought it was interesting how similar the rear suspension is to the current platform - looks like the parts may even be interchangeable. Pretty nice to have things like rear lower control arms be interchangeable because there's already a bunch of aftermarket options. Rear coils and shocks might even be interchangeable. That will keep costs reasonable on a lot of parts.
 
He and I think a lot alike. I don't always agree with some of his analysis, but I think he does a great job on his videos. Far better than most!

In the video he discusses the articulation spec vs real world and the differences. My bet is that Toyota's number is based on a calculated max that includes the compression of the bump stops as what they consider fully articulated and in the real world at slow speeds or no speed you wouldn't actually be compressing through the bump stops or possibly even touching the bump stops. So there's more up travel in the suspension and flex in the rubber bushings than is used during a low speed mogul or static measurement. That probably accounts for the difference in the two measurements.

I thought it was interesting how similar the rear suspension is to the current platform - looks like the parts may even be interchangeable. Pretty nice to have things like rear lower control arms be interchangeable because there's already a bunch of aftermarket options. Rear coils and shocks might even be interchangeable. That will keep costs reasonable on a lot of parts.
Toyota might use CAD data from suspension geometry instead of measuring it using tape measure. Or do it at full GVWR, which would compress the spring and twist KDSS bar some more.

As for suspension compatibility all 300 series product are technically compatible. The weight is the only difference and might require slightly lower spring rate.

Total Chaos already have long travel for 300 series. Sequoia and Tundra also very similar. Rear shocks are similar to 80 or even 200 series. Dobinson 4" lift for 80 series was marketed to fit Tunda before they come up with specific part number.
 
It is worth noting that Toyota published a number but the very person who would know was not willing to disclose how it was calculated. That I assume / hope will come later at some point.
 
It is worth noting that Toyota published a number but the very person who would know was not willing to disclose how it was calculated. That I assume / hope will come later at some point.
It's odd that he wouldn't disclose it. I figured it was a language barrier issue that he wasn't sure he could get it correctly repeated in English. But I don't speak Japanese.
 
It is worth noting that Toyota published a number but the very person who would know was not willing to disclose how it was calculated. That I assume / hope will come later at some point.
I think the reality is that a lot of the off road performance measurements like articulation and ground clearance don't have an industry standard calculation and manufacturer's don't disclose how they calculate. Maybe Toyota does some calculation based on suspension arm geometry vs the Kai's real world measurements with bump stops, bushings, shock length, gravity, etc involved?

The point is that Lexus published an articulation number, which is relatively uncommon for any truck, to show a large increase in articulation for the 550 vs the 460. Kai's real world measurements for the 460 and 550 are lower than Lexus' published numbers for both, but confirm there is a large increase in articulation between the two. That is pretty cool.
 
I like that guys video's. He does a good job overthinking things and bringing the information into his videos. About time someone stops the GX while flexing and gets out and actually looks underneath on a test drive. It's cool he's actually doing measurements and questioning the chief engineer while he has the chance.
I'm looking into the GX in the next few years. The wifey is really liking the Luxury+. I don't see this ever being an off-road machine, at least until she gets bored and moves on to another vehicle and I can dig in LOL. With that said, the fact they chose NOT to use E-KDSS on this L+ model kind of sucks, or does it? I assume you could go with the LC front disconnect at some point and easily adapt it to the GX? Would later modifying the suspension with the NON E-KDSS actually be a good thing? I'm thinking maybe enough to do 35's at some point and not much more. Maybe add in a rear locker and re-gear at most. I drove the 80 for nearly 20 ears with a mild lift and 35's and really miss it. I know the KDSS is a different system but anyone that has had to deal with this on the current GX be able to speak to this?
 
I think the reality is that a lot of the off road performance measurements like articulation and ground clearance don't have an industry standard calculation and manufacturer's don't disclose how they calculate. Maybe Toyota does some calculation based on suspension arm geometry vs the Kai's real world measurements with bump stops, bushings, shock length, gravity, etc involved?

The point is that Lexus published an articulation number, which is relatively uncommon for any truck, to show a large increase in articulation for the 550 vs the 460. Kai's real world measurements for the 460 and 550 are lower than Lexus' published numbers for both, but confirm there is a large increase in articulation between the two. That is pretty cool.

And that's fine but he should be able to explain whatever standard they used. The added tidbit is that he seemed to agree on how Kai He got his measurements.
 
I like that guys video's. He does a good job overthinking things and bringing the information into his videos. About time someone stops the GX while flexing and gets out and actually looks underneath on a test drive. It's cool he's actually doing measurements and questioning the chief engineer while he has the chance.
I'm looking into the GX in the next few years. The wifey is really liking the Luxury+. I don't see this ever being an off-road machine, at least until she gets bored and moves on to another vehicle and I can dig in LOL. With that said, the fact they chose NOT to use E-KDSS on this L+ model kind of sucks, or does it? I assume you could go with the LC front disconnect at some point and easily adapt it to the GX? Would later modifying the suspension with the NON E-KDSS actually be a good thing? I'm thinking maybe enough to do 35's at some point and not much more. Maybe add in a rear locker and re-gear at most. I drove the 80 for nearly 20 ears with a mild lift and 35's and really miss it. I know the KDSS is a different system but anyone that has had to deal with this on the current GX be able to speak to this?
I think you would have a lot of work to try to get 35s to fit. Personally, my back hurts just remembering when I rotated 33s on my 200. No thank you very much.
 
Very good video and well explained.

I'm sure the chief engineers and road crew were like "wtf is this dude doing" when he started to pull out his paper templates and tape measure.

I agree that the way to look at this is the relative differences and not the absolute values. There is so much slop in how he was measuring that you would easily get a few inches one way or another depending on where he measured....again, going back to standards.

My main take away is that they really spent the time and engineering to improve the platform in multiple ways (rather than a one trick pony)...Lexus knew exactly where this truck was/is going!
 
Last edited:
Gents,

One of the best things of my 200's have been the KDSS not only off road but MOSTLY on road for manners, I absolutely adore it ! Question: would the eKDSS help on road manners same waay 200's KDSS does ?

Thx. 🫂
 
Gents,

One of the best things of my 200's have been the KDSS not only off road but MOSTLY on road for manners, I absolutely adore it ! Question: would the eKDSS help on road manners same waay 200's KDSS does ?
Yes. That's the whole point.
 
Gents,

One of the best things of my 200's have been the KDSS not only off road but MOSTLY on road for manners, I absolutely adore it ! Question: would the eKDSS help on road manners same waay 200's KDSS does ?

Thx. 🫂
E-KDSS should be a nice upgrade to the concept since the front and rear bars operate completely independent of each other and there are geometry/mounting improvements. If I understand correctly that should let E-KDSS react faster and improve comfort/head toss in those "mid speed" articulation scenarios where you have the default stiff sways but need one to unlock (i.e. hitting a pothole going 30). It may also eliminate or at least greatly reduce the KDSS lean issue since you can't create the hydraulic imbalance that causes it now.
 
E-KDSS should be a nice upgrade to the concept since the front and rear bars operate completely independent of each other and there are geometry/mounting improvements. If I understand correctly that should let E-KDSS react faster and improve comfort/head toss in those "mid speed" articulation scenarios where you have the default stiff sways but need one to unlock (i.e. hitting a pothole going 30). It may also eliminate or at least greatly reduce the KDSS lean issue since you can't create the hydraulic imbalance that causes it now.

For me, it's less the interconnect and more the fact that geometry has improved. The asymmetry of the solid link and single ram of the 460 was always going to introduce some problems, but the single pivot and dual energized rams fixes that and could potentially make it stronger. It's more complicated, but it makes sense.
 
For me, it's less the interconnect and more the fact that geometry has improved. The asymmetry of the solid link and single ram of the 460 was always going to introduce some problems, but the single pivot and dual energized rams fixes that and could potentially make it stronger. It's more complicated, but it makes sense.
I feel like the E-KDSS design is more conducive to lifting since there is a ram for each side and end links instead of directly bolting to the LCA. In my mind that means you can just use longer end links or some kind of spacer to match your lift height and everything stays equalized side to side. I could be very wrong.
 
I feel like the E-KDSS design is more conducive to lifting since there is a ram for each side and end links instead of directly bolting to the LCA. In my mind that means you can just use longer end links or some kind of spacer to match your lift height and everything stays equalized side to side. I could be very wrong.
That front link design is the same as 200 series. The lever arm in the rear are used in 200 series front.
Not being linked front and rear should eliminate balance issues when lifting. The issue is motion ratio for front and rear are not the same so they create pressure imbalance.

To me the greatest benefit of KDSS is on the road. My KDSS equipped GX470 on 35 still corners pretty flat. Off road the linked front and rear always give great balance. Not the greatest flex but the vehicle feels balanced even when lifting wheels. I was able to use 10" travel rear shocks and it add quite a bit of rear flex.
 
Last edited:
To me the greatest benefit of KDSS is on the road. My KDSS equipped GX470 on 35 still corners pretty flat. Off road the linked front and rear always give great balance. Not the greatest flex but the vehicle feels balanced even when lifting wheels. I was able to use 10" travel rear shocks and it add quite a bit of rear flex.
This is what is confusing to me. Why wouldn't they include it on the Luxury+ model then?
 

Users who are viewing this thread

Back
Top Bottom