F*&king lean! KDSS. Go back to stock? Is there an exhaustive KDSS thread, wiki, faq?

OK, still dealing with the lean. 2016 Trail with KDSS.

My problem is that I bought the truck this way, so I have no idea what the previous owner did. It's lifted, and it looks like stock shocks + higher springs in the front, Taller springs and 5100s in the back. looks like a 2 inch lift.

The dealer serivced KDSS before sale. It was refilled with fluid and checked for operation (static check) . I have no idea what that really means. Does anyone Do they just run a program on the valve actuators to see if the valves open and close? Do they test the cylinder/ram operation (i doubt it)

The truck started with about an 1.25 inch lean to pax side. KDSS spacers and a .25 inch strut spacer brought it down to 1/2 inch, but it keeps changing. it's not static. That's driving me batty. Also it feel like the truck leans more in turns to the left vs turns to the right, like the front behaves asymetrical in sway. Is there a way to test this? Ram operation?

I'm thinking of ripping the shitty lift out and putting in stock parts at this point.

I spoke to Dom (DrKDSS) and his suggestion is to deactivate kdss at the fuse/switch and drive the truck around, making sure to get some high speed turns in. That is supposed to leave the valves open and sort of force a calibration on the system. A more dynamic way than just unscrewing the valves a little and letting fluid go between the two loops by itself.

Any thoughts on the above?

 

I'd start with his suggestion.

 

KDSS lean can happen with or without lift. Per my trusted 4x4shop guy loosening the KDSS valve and using the jacks is what they use to correct it. If you are local to CO I can share the contact.

 

Rip off all the aftermarket shit and put in new stuff. Then you know exactly what you have.

 

Do what Dr. KDSS suggested.

 

OK. Conceptually I understand what he is suggesting. How do I achieve this practically? Is it just pulling the fuse when the vehicle is stopped? Would that leave the valves in open position? Which fuse?

 

That would be a great question for him to answer. I know he has helped a lot of people and his knowledge on the KDSS system is beyond anyone I know. Granted, there is minimal issues with KDSS and there is also the possibility that the problem is with your suspension and not the KDSS.

 

install 6112s. The staggered settings for D & P eliminate the lean..

 

@silvercow you can either look at his youtube instructions of installing his KDSS switch - then you'll see where the kdss connection is.
underneath the steering wheel, theres this plug for kdss. all you have to do is unattach it and you're kdss is disabled.
or you can locate the fuse in the kickpanel and pull that out.
OR buy his switch kit if you plan on going offroad - it makes it a bit more pleasant.

but yes, follow his instructions as he's very knowledgable.

if the front shocks are adjustable via C-CLIP then see if that is set the same (driver/pass). Check the rear springs too if any spacers were added. you'll need to remove your spare tire to really get in there.

 

lol drkdss markets his solution as a panacea for a issues…

Search on YouTube.. lots of kdss lean topics.

 

I’ve got pretty much all the DRKDSS stuff on my T4R. I’m a fan. The 2 things that did the most to correct my lean was a Dobinsons spacer on my rear passenger side coil and the DRKDSS bypass switch. Being able to press a button and go take some turns or hit some bumps brings things back to level-ish. I’m always 0.25-0.50 inch higher on driver side, but it was like that stock also.

Also really like the DRKDSS BOTCK and all the other goodies I’ve added from him. Does what he says it does in general.

 

Serious question, do you know you have a lean because of noticeable performance or handling issues, or drive quality? Or do you know you have the lean because you broke out a tape measure? I ask because I know that I have the KDSS lean only after reading threads like yours and so out of curiosity I broke out a tape measure. Otherwise, I would have never noticed. My suspension is 100% stock, unless you consider KO2 tires.

 

KDSS is worth all the hassle. FIX IT!

 

Are you sure it's not just the normal 4R lean to the driver's side?

 

I broke out the tape measure. Also, my butt dyno is telling me that the truck rolls more to the right (left turns) than it does to the left (right turns) . I'm trying to measure this and confirm, or eliminate. Have not done the KDSS shut off and forced calibration, per Don's suggestion, yet.

As a backup, I just picked up a set of stock springs and shocks from a 21 TRD OR for $300. Thay had 9k miles on them when they were replaced, per the seller. Since my truck is coming up on 92k, i might just rip out whatever lift the previous owner slapped in and go back to stock with that hardware.

 

Throwing money at it isn’t the best approach. I seriously doubt the shocks alone are causing the lean. Maybe a spring issue if the KDSS is eliminated as a causal factor.

 

Well, the suspension I picked up is complete, OEM struts/shocks+springs, and the fronts are already assembled, so its a relatively easy swap. The truck had a KDSS fault when the dealer took it in. Toyota serviced KDSS. Flush, refill, check solenoid valve (shutter valve) operation. So in theory it is supposed to be good, but I am not sure i trust them. I can't get a straight answer if there is a test they perform , especially if the truck has been lifted and the kdss rams are not in their stock neutral positon.

So, eliminating KDSS as the source of the lean is my next goal. One approach I'm considering is to disconnect both sways completly from both end links and driving the truck around a little around my neighborhood to see is the springs/shocks themselves are introducing a lean or if it is gone. If gone, it would mean the sway or sways and thus KDSS is introducing it.

 

Stock GX460 KDSS lean issues fixed by changing spring (forgot which side) per Lexus warranty service instructions.

 

Lifting doesn’t change the rams from neutral, it just rotates the bars within the bushings. If you look at it for a while, you’ll see that it wouldn’t work any other way. Otherwise when your truck went over compression dips, the handling would be scary dangerous. The rams and sways only engage if there is a twisting force across the axle.

 

Can you post pictures of the lean on your 4R?

 

I thought as well, but then why is pax side lean so common on lifted KDSS trucks? KDSS and panhard bar are the only things i can think of that are asymetrical in their design.

 

You don't stagger them with KDSS.

 

I don't think it's as common as these forums make it seem. I definitely happens. But, you'll also notice that a good portion of the comments about lean are from people that don't even have kdss, but they knew a guy who knew a guy, etc.

 

I have a theory about that. I spent time doing some careful measuring, and while there is some variability, I noticed that my truck is pretty level when I’m just done driving and engine is idling. Once I turn it off and wait a minute or two, I’ll get some passenger side lean.

My theory is that the accumulators bleed off after the engine is turned off and put some pressure on the rams, extending them a small amount, causing the parked lean that people notice.