RET2
SILVER Star
This thread gives me the creeps as much as the one about installing a Tesla type display/radio. 
KDSS Stupid (1 Viewer)
- Thread starter kcjaz
- Start date
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cboyd
GOLD Star
yes, significant lean after a lift by a competent shop with known kit (Dobinson) - but no known issues beforehand. clean CPO 2015 with 70k miles... after the lift was done, no matter of adjusting, blocking, etc corrected the lean. took it to the dealer and they only have one remedy - purge and re-pressure. The procedure mostly correctly the lean, but i also had to add a 1/4 spacer to the driver front to get it 100% leveled.
kcjaz
SILVER Star
- Thread starter
- #23
They will have to put me on suicide watch if that happens to me.
Its going to cost me $1100 to get the KDSS flushed, filled and bleed. If I then install my new BP-51 and have some lean issue that takes another $1100 at the dealer to repeat the KDSS flush, fill and bleed, I'll end up with the world's most expensive BP-51 set up ever. Not really what I was going for.About the $1100. I knew it was going top hurt but that seems crazy. They are saying its 8 hour job and takes two. Hey @bloc, do you have the FSM procedure? Seems like you have at least seen it. Is it really an 8 hour job? Does that seem reasonable?
On a side note, the dealer does have the pump kit on his shelf. Its the fluid he has to get and that will take 3 or 4 days. It takes 6 qts. Seems like a lot. Thank God you don't have to replace it every 10,000 miles.
Also, the dealer doesn't want to fix my KDSS after I put on the BP-51. I think they ultimately !)would after I sign an "all bets are off and you are on your own with what ever happens" kind of document. Basically, if there is any issue, they will say it is due to the aftermarket parts. I think the reality is that I'm there anyway. It is making more sense to me to install the BP-51 parts now, while I have already drained the KDSS and have the dealer do their $1100 service after. There seems to be enough BP-51's out there to make me think issues like @cboyd described aren't likely but installing the BP-51 first and then fixing the KDSS seems like the lowest risk/best option to me. Anyone disagree? (If I actually knew anything, I would be in this situation)
bloc
SILVER Star
They will have to put me on suicide watch if that happens to me.
About the $1100. I knew it was going top hurt but that seems crazy. They are saying its 8 hour job and takes two. Hey @bloc, do you have the FSM procedure? Seems like you have at least seen it. Is it really an 8 hour job? Does that seem reasonable?
On a side note, the dealer does have the pump kit on his shelf. Its the fluid he has to get and that will take 3 or 4 days. It takes 6 qts. Seems like a lot. Thank God you don't have to replace it every 10,000 miles.
Also, the dealer doesn't want to fix my KDSS after I put on the BP-51. I think they ultimately !)would after I sign an "all bets are off and you are on your own with what ever happens" kind of document. Basically, if there is any issue, they will say it is due to the aftermarket parts. I think the reality is that I'm there anyway. It is making more sense to me to install the BP-51 parts now, while I have already drained the KDSS and have the dealer do their $1100 service after. There seems to be enough BP-51's out there to make me think issues like @cboyd described aren't likely but installing the BP-51 first and then fixing the KDSS seems like the lowest risk/best option to me. Anyone disagree? (If I actually knew anything, I would be in this situation)
I have seen the procedure and while it didn’t quote time, it did seem pretty involved. The system doesn’t hold anywhere near 6 liters, but you actually flush fill and drain again so many times a lot of good fluid is pushed back out. Plus parts where you go to the 1015psi for x minutes then lower pressure and bleed.
It does sound like your best bet is just throw the suspension on and have them do the KDSS job then. That said I would NOT drive the truck until that is done. You effectively won’t have sway bars.
kcjaz
SILVER Star
- Thread starter
- #25
Thanks and yep, no high speed driving until this is fixed. I will say though that when I drove it to the dealer (city streets, no highway) I couldn’t really notice any difference. Maybe this is because I lost the fluid from the rear most valve and that only affects the rear. The other one was open at the time so I would think both would be affected. IDK.
cboyd
GOLD Star
I think mine had some underlying issue that wasn’t exposed until the lift went on... I doubt if you did the procedure and then the lift that you’d have issues. the KDSS is a pretty simple concept and implementation. Not too much to go wrong, as as such, the dealers don’t see problems and aren’t that versed on it.They will have to put me on suicide watch if that happens to me.
About the $1100. I knew it was going top hurt but that seems crazy. They are saying its 8 hour job and takes two. Hey @bloc, do you have the FSM procedure? Seems like you have at least seen it. Is it really an 8 hour job? Does that seem reasonable?
On a side note, the dealer does have the pump kit on his shelf. Its the fluid he has to get and that will take 3 or 4 days. It takes 6 qts. Seems like a lot. Thank God you don't have to replace it every 10,000 miles.
Also, the dealer doesn't want to fix my KDSS after I put on the BP-51. I think they ultimately !)would after I sign an "all bets are off and you are on your own with what ever happens" kind of document. Basically, if there is any issue, they will say it is due to the aftermarket parts. I think the reality is that I'm there anyway. It is making more sense to me to install the BP-51 parts now, while I have already drained the KDSS and have the dealer do their $1100 service after. There seems to be enough BP-51's out there to make me think issues like @cboyd described aren't likely but installing the BP-51 first and then fixing the KDSS seems like the lowest risk/best option to me. Anyone disagree? (If I actually knew anything, I would be in this situation)
that said, since its already an issue, I’d put the lift on and then have the procedure done. Just be careful driving it from place to place. The lack of a sway bar can produce dramatic body roll!
cboyd
GOLD Star
Btw, $1100 seems high. I was quoted $850 and they did it in less time than estimated So I only paid just north of $650.
6 liters of suspension fluids at $20 /per
6 liters of suspension fluids at $20 /per
Is it the same fluid as what is used in the AHC system? Wonder what's so special about it.
CharlieS
GOLD Star
I met guys in the gulf that disconnect the sway bars...
Not like I'm in some hurry to to that, but I wonder if there is a traditional anti-sway bar option available to retrofit, like from another ROW model? I only suspect that mining spec and UN utility models come with a more traditional (low maintenance) option. That much less to fail, break, maintain...
Like these (partssouq for a GRJ200L-GCMRK):
Not like I'm in some hurry to to that, but I wonder if there is a traditional anti-sway bar option available to retrofit, like from another ROW model? I only suspect that mining spec and UN utility models come with a more traditional (low maintenance) option. That much less to fail, break, maintain...
Like these (partssouq for a GRJ200L-GCMRK):
| 4880560120 | BAR SUB-ASSY, REAR STABILIZER |
| 4881160290 | BAR, STABILIZER, FRONT |
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bloc
SILVER Star
The LX570 has traditional sway bars and I believe they bolt in. Thing is, AHC can do some active roll control so i’m not sure how those bars would compare in diameter and stiffness to ROW 200s without KDSS or AHC.
What causes the lean? Do the actuators change their positions, heights? I'm about to put a lift on my 12 and really would hate to have to deal with this. When shopping for a lift, I noticed a lot of spacers and spring offsets in order to correct the lean. Why is this such a problem?
bloc
SILVER Star
You have a 2012?
It is generally considered an inability to balance the pressures on the top/bottom of both KDSS cylinders, which puts force on the sway bars and causes the truck to lean. That is the point of the 4x4 trick, to cause an imbalance the other way.
I suspect the problem isn’t always there though. Possible candidates (in my head) are pressure from the bushings on the sway bars themselves, suspension pivot bushings not being in a neutral position when torqued, and possibly other things I’m not thinking of.
@Whizzer929, for stock springs the fronts are equal height but the rears are different lengths because right side (passengers side) in the US is heavier than the left side (US driver's side). The slightly longer spring makes the vehicle level (or very close to it) from the factory. factory springs are 500#/in in the front, 170#/in in the rear. When you to go a lift with springs of different coil rates, particularly in the rear, you may develop a lean.
Think of it this way (simplistically) - if your factory spring is 170#/in and 11" tall on the left but 12" on the right, and the left spring compresses 3" when you put an unladen vehicle on the ground (meaning 170 x 3 or roughly 510# of compression) but the right spring compresses 4" (because it's 170 x 4 or about 680#). Now you swap in 240# springs, so the left only compresses 2.125" (510/240) and the right now compresses 2.83" (680/240) suddenly you have .71" of difference left-to-right where previously you were level. And now that difference will change depending on the rear cargo load - whether it's fixed static weight (like drawers, or a rear bumper), variable weight (like your kids or dog sometimes riding in the rear and sometimes now), or highly dynamic weight (like a set of bikes hanging off the trailer hitch). Now maybe the uninstalled spring length is different (not 1") like the factory length, but even if you compensate in the above example by shortening the longer spring to get you level when unloaded you may still have left-to-right imbalances when you start adding accessories to the left or right side of the vehicle). So you can see why trim-packers (spacers) might be helpful as every vehicle can have different loads and use cases in which available spring rates can only approximate the right configuration.
Note that the above spring rates in #/in are correct to the best of my knowledge but the spring *lengths* are just a hypothetical example.
Think of it this way (simplistically) - if your factory spring is 170#/in and 11" tall on the left but 12" on the right, and the left spring compresses 3" when you put an unladen vehicle on the ground (meaning 170 x 3 or roughly 510# of compression) but the right spring compresses 4" (because it's 170 x 4 or about 680#). Now you swap in 240# springs, so the left only compresses 2.125" (510/240) and the right now compresses 2.83" (680/240) suddenly you have .71" of difference left-to-right where previously you were level. And now that difference will change depending on the rear cargo load - whether it's fixed static weight (like drawers, or a rear bumper), variable weight (like your kids or dog sometimes riding in the rear and sometimes now), or highly dynamic weight (like a set of bikes hanging off the trailer hitch). Now maybe the uninstalled spring length is different (not 1") like the factory length, but even if you compensate in the above example by shortening the longer spring to get you level when unloaded you may still have left-to-right imbalances when you start adding accessories to the left or right side of the vehicle). So you can see why trim-packers (spacers) might be helpful as every vehicle can have different loads and use cases in which available spring rates can only approximate the right configuration.
Note that the above spring rates in #/in are correct to the best of my knowledge but the spring *lengths* are just a hypothetical example.
Interesting. I've read somewhere in this forum from a reputable source that KDSS was designed to attempt to "rebalance" the system over time. So if your driveway is on a slope the system may actually cause a small lean over time, and the KDSS rebalance trick should quickly fix that. Wish I could find the link right now but I want to say it was the KDSS designer who noted that
To the OP: @kcjaz, I would just have the dealer re-pressurize the system now. When you go to put the BP-51s on, just be careful not to un-screw more than 3 turns - put in the allen key, note where it's pointing, and then rotate around 1 time, 2 times, and then as you approach the 3rd rotation STOP. In my experience it only takes 2 turns but YMMV. Note that if you lift all 4 wheels off the ground you'll be able to tell when the wheels quickly droop.
gaijin
GOLD Star
You have a 2012 LX570, right?
Last I checked, LX570 does not have the KDSS system.
HTH
gaijin
GOLD Star
@Whizzer929 has a 2012 LX570. No KDSS on the LX, right? Or am I having a COVID-influenced brain fart?
Hi BlocKDSS pump
what kind of KDSS fluid they use? Can I use the Lexus AHC suspension fluid.
bloc
SILVER Star
The method I use to look up part numbers doesn’t list fluids, unfortunately. No clue whether AHC fluid will work, but I wouldn’t try it unless you can confirm that is what toyota uses.
Some 4runners have KDSS and by virtue of those being far more common, there is quite a bit of info online about how to work on their systems. Might be worth digging around in those forums to see if you can locate a real KDSS fluid part number.
Out of curiosity, why do you need it? Did your system leak? And will you be pressurizing/bleeding it yourself?
Yes I’m going to do it myself. Replaced KDSS unit because of rusted hex bolts. Called 6 dealers around my area and all 6 don’t know what KDSS do. Do you also know the SST tool part number for LC200?
