Wow...did not know that. So, you have CRAWL and a rear locker on one vehicle?
2020 Toyota Land Cruiser vs. 2020 Lexus LX 570 Suspension Flex Test: A 200-Series Frame-Twist Battle (2 Viewers)
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Wow...did not know that. So, you have CRAWL and a rear locker on one vehicle?
Locker vs CRAWL please correct me if I get this wrong. Locker distributes Torque to Left and right side of Axle Equally. So if you loose traction on one side the other side is still turning. A no locking diff allows left and right side to rotate at different speeds and side with less grip will rotate at input speed to axle the other wheel with grip will likely not rotate.
CRAWL uses the application of brake. Each wheels brake is independently managed by software. If engaged a wheel that is spinning freely with get brake applied this will force open diff to send torque to not turning wheel.
Thanks
CRAWL uses the application of brake. Each wheels brake is independently managed by software. If engaged a wheel that is spinning freely with get brake applied this will force open diff to send torque to not turning wheel.
Thanks
Yes. CRAWL is like an advance version of traction control. But CRAWL is very aggressive at braking the "slipping" wheel almost immediately. So, when using CRAWL, you basically get almost zero wheel spin...near locker level in terms of traction, without the limitations of a locker.
Rather than talking about a locked diff in terms of torque split, I think an easier way of thinking about it is simply that when a diff is locked both output shafts turn at the same speed.
gaijin
GOLD Star
So... what would happen if one engaged CRAWL on their LC200 and then went up the flex test ramp?
Would it crawl its way all the way to the top?
If so, what's the real meaning of all these flex comparisons if there is an onboard feature that allows better performance if all we need to do is engage it?
Just sayin'
Would it crawl its way all the way to the top?
If so, what's the real meaning of all these flex comparisons if there is an onboard feature that allows better performance if all we need to do is engage it?
Just sayin'
bloc
SILVER Star
Yes, even if you can keep progressing down the trail due to traction being where you need it, articulation allows you to do more of it with four wheels on the ground providing stability. A wheel dangling in the air looks cool but if the weight shifts that direction things can go bad quick.
My issue with atrac vs a locker is the systems tendency to almost completely stop the spinning tire. When this happens it effectively halves your diff ratio to the wheel you have on the ground doing the driving. Almost like momentarily taking it out of low range on that axle. With an engaged locker none of this occurs.. the wheel without traction just spins along as if it were pressed into the ground, only it isn’t.. most of it’s load and traction has been transferred to the other wheel on that axle. I believe this is why most of the demonstration videos and my experience show our faux lockers to seek to have much more drama getting the job done than a locker would.
My issue with atrac vs a locker is the systems tendency to almost completely stop the spinning tire. When this happens it effectively halves your diff ratio to the wheel you have on the ground doing the driving. Almost like momentarily taking it out of low range on that axle. With an engaged locker none of this occurs.. the wheel without traction just spins along as if it were pressed into the ground, only it isn’t.. most of it’s load and traction has been transferred to the other wheel on that axle. I believe this is why most of the demonstration videos and my experience show our faux lockers to seek to have much more drama getting the job done than a locker would.
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havent chip in for a while, here's a video of the system at work, not sure crawl or Limited Slip, it works like a charm.
i was offroading with3 other dudes, one in hilux, VDJ200 with AHC and 80 series quipped with 35", only me and him able to overcome the obstacle (sick angle, the vid didnt do justice!)
i was offroading with3 other dudes, one in hilux, VDJ200 with AHC and 80 series quipped with 35", only me and him able to overcome the obstacle (sick angle, the vid didnt do justice!)
bloc
SILVER Star
Great video.. shows crawl/atrac doing what it’s supposed to do.. keep the low traction wheel from spinning wildly, but let it spin at the rate of everything else. On some surfaces it has a harder time with this.
It is still a great system, my point is merely that a locker still has its place depending on what you are doing.
Edit: crawl IS atrac Plus throttle and selectable speed control.
It is still a great system, my point is merely that a locker still has its place depending on what you are doing.
Edit: crawl IS atrac Plus throttle and selectable speed control.
I know...but previous ATRAC iteration allowed too much wheelspin which led to loss of momentum, esp when going up a rockledge. CRAWL is near instantaneous in getting power to the wheel(s) with traction.
I was under the impression the LX570 had AHC and KDSS, not fixed skinny stabilizer bars.
Both AHC and KDSS utilize technology originally licensed from Tenneco Kinetic suspension technology.
KDSS as Toyota brands it, is a passive form of cross-linked hydraulic actuators, that acts upon the stabilizer bars.
AHC is active KDSS on steroids and has cross-linked hydraulic features at its core, but also has height, damping, multi-spring rate functions, all actively managed by software. These act directly on hydraulic actuators in place of traditional dampers at the wheels. It then has skinny stabilizer bars as augmentation. Just as it has tender springs to augment load support.
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Does AHC have cross-linking feature? If one wheel goes up, then does the other wheel (on same axle) gets actively pushed down by the AHC???
AHC does not do anything to anti-roll bars, right? Lexus LX has fixed skinny anti-roll bars as mentioned above.
I don't see how AHC is KDSS on steroids...two different system. Maybe same company/developer. But two very different system.
Lexus LX does NOT have KDSS. Just AHC.
Toyota Land Cruiser does NOT have AHC. Just KDSS.
Each have its benefits. I don't consider either one to be better than the other...just different purpose.
At least here in USA. Not sure about abroad.
bloc
SILVER Star
Teckis why wouldn’t there be damping force control actuators on the rear circuits of the system?
Yeah, sorry, don’t see it. And as can be seen in video at beginning of this thread, there is no such “active” cross-linking where one side is up pushing the other side down (on same axle).
Such meanness from you.
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AHC is indeed cross-linked.
bloc
SILVER Star
Study the diagram. Right rear and left front are a circuit, left rear and right front are a circuit. When RR/LF are stuffed the center suspension control cylinder can send the increased pressure in that side to the other, cross-linking the suspension. It isn’t automatic as in KDSS but the suspension position sensors tell the control computer opposite corners are getting stuffed and enables the cross linking.Yeah, sorry, don’t see it. And as can be seen in video at beginning of this thread, there is no such “active” cross-linking where one side is up pushing the other side down.
Such meanness from you.
