Thanks JBHorne. While it's not an apples to apples comparison, it is another valuable perspective (all who post to these forums are credible!). I don't think I originally mentioned this in my earlier post, but I am inquiring about the comparison of XREAS vs. KDSS specifically for on-road driving. It seems that's what XREAS is marketed for, vs. KDSS for off-road, but overall w/ the comments it seems that KDSS is a superior system and outperforms XREAS regardless of terrain. Hmm? I notice KDSS is in the higher-end Lexus cousins, and those could be considered more luxury/Limited-esque, but perhaps this would bring the price tag too high to add KDSS in place of XREAS on the 4R Limited?
The problem is that the two systems are completely different. They accomplish different things.
First, you cannot get a Limited with KDSS. The limited is kind of a joke and I say this owning one. With 20" rims, this thing was never designed to offroad in stock form IMHO. The limited is designed for looks and on road handling, where XREAS shines. KDSS is an offroad system.
Here's the difference: XREAS is an on road suspension system wherein the mono-tube shocks are cross-linked. When cornering, hydraulic fluid is pumped in an X pattern from front left to rear right and from front right to rear left to prevent body roll. The XREAS shocks are very high pressure shocks and thus are much stiffer than the twin-tube shocks on the SR5 and trail edition (both the SR5 and trail use the same shocks). XREAS does nothing to absorb bumps.
KDSS is not a suspension system but rather a hydraulic sway bar disengagement system. KDSS basically disengages the sway bar via hydraulics (maybe partial electronics as well) for good articulation offroad, and keeps it engaged (default) on road. Thus, you get the best of both worlds.
The advantage of KDSS is that you can replace your suspension with whatever you want and it will not effect KDSS as it's a hydraulic cylinder on the sway bar, nothing to do with the suspension.
In theory, I believe KDSS is a superior system for a vehicle that will see both pavement and offroad. On my 200, the KDSS is great because it allowed me to lift the vehicle with new struts/springs with nothing lost. With the XREAS system on my 4Runner Limited, my only option is to either ditch the XREAS or use spacers and new springs, leaving the struts. I'm not planning on doing anything to it as it's my travel vehicle now (I only get 13mpg on the highway in the 200 at 80MPH. At 130MPH, I didn't even look at the mpg reading :lookout
The disadvantage to XREAS is that one shock cannot be replaced as it's an entire system. If one blows for some reason, the entire system would need to be replaced. These shocks however should last the entire life of the vehicle.
Theoretically, both systems could live together, but I don't see the point.
The answer to me is simple. For on road only, you want XREAS. For offroading, you want KDSS, for mixed you either want KDSS or neither. I do not like XREAS for offroading do to it's stiffness. Others may disagree, but drive all three and you will feel the big difference.
