Disabling the AHC and AVS systems, no warning lights. (2 Viewers)

[bloc]

Not saying to apply KDSS to new platforms, but I think the LC community can use some of that ingenuity you've brought to LXs.

They need a more aggressive and wholistic solution for a front relocation bracket. Probably something that brings the sway bar 1.25"-1.5" forward. Along with an A-Arm spacer bracket to better mount the end link to the outside LCA bucket. There's probably other unique ways to improve space constraints that haven't been explored yet. I would recommend a geometry that reduces KDSS motion ratio to increase flex, but still keep the anti-sway goodness.

There might also be a need for longer end links or to space the whole system down to better accommodate droop travel angles.

Maybe blasphemy, but KDSS delete! With new brackets to support standards sway bars.

While he's at it, one thing to consider with 200-series KDSS is significantly increased travel in front can lead to interference between the front of the KDSS arm and the body mount. Mine does this with King 2.5s but no relo bracket.

I suspect that people running so much travel often have KDSS relo brackets that also space the sway bar down and avoid this interference, but depending on motion ratio and wheel travel issues that is somewhere that should be kept in mind.

 

[B Hans]

Finally have everything situated and new wheels/tires put on. I didn't take good measurements ahead of time, but best I can tell ended up with about 1.5" of lift in the front and 1" in the rear. Front Suspension: Total Chaos Upper Arms, 2.5" Fox Coilovers w/ remote reservoir. Rear Suspension: Icon progressive coil springs, 2.5" Fox reservoir shocks. Couple hundred miles of driving and no issues so far. Ride feels much better, feels almost as firm as the Sport setting, though less jarring over bumps with less upset of the vehicle. I don't feel like the body roll is any worse than stock but I'll keep an eye on that as I get some more miles on it to see if I want to go with a different swaybar. My initial thoughts are the shocks are pretty well valved but if I'm being particular could probably use some more compression damping in the rear and maybe a little less rebound in front. Need to get some offroad miles in before I mess with anything there though. I thought I would miss AFS, but I don't really notice it's missing (the HID conversion helps). Overall, much more happy with it and looking forward to seeing how it does in the backcountry on callouts, etc. Big thanks to Turbo8 for showing this could be done!

 

[jbyrd78]

It's good to see a thread on deleting the AHC on a LX570 b/c I am possibly looking at purchasing a 2015 LX570 that has just had a new AHC system installed in it with only 100,000 miles on the ODO.
My question I want to ask, is if I end up purchasing this LX570, and end up having issues with the AHC, and I want to install stock 200 series Land Cruiser suspension on the LX570, that is possible correct? I just want to make sure I am understanding things correctly.

 

[trudd]

It's good to see a thread on deleting the AHC on a LX570 b/c I am possibly looking at purchasing a 2015 LX570 that has just had a new AHC system installed in it with only 100,000 miles on the ODO.
My question I want to ask, is if I end up purchasing this LX570, and end up having issues with the AHC, and I want to install stock 200 series Land Cruiser suspension on the LX570, that is possible correct? I just want to make sure I am understanding things correctly.

To add to this - what are the minimum parts required for an AHC to Stock LC swap besides shocks and springs?

I've seen mention of non-KDSS sway bar and different control arms, though I'm not sure if these are necessary. I've also read that you'll need new top mounts (are these called sub-assemblies?) for the front shocks, since the assembly on top of the AHC shock is a different diameter and cannot be reused.

Does anyone have a parts list for a minimum viable swap to stock LC suspension?

 

[xhrix123]

To add to this - what are the minimum parts required for an AHC to Stock LC swap besides shocks and springs?

I've seen mention of non-KDSS sway bar and different control arms, though I'm not sure if these are necessary. I've also read that you'll need new top mounts (are these called sub-assemblies?) for the front shocks, since the assembly on top of the AHC shock is a different diameter and cannot be reused.

Does anyone have a parts list for a minimum viable swap to stock LC suspension?

Yes you can, and only shocks and springs necessary.

You can always add and change other things but not necessary.

Of course you wont have kdss

 

[jbyrd78]

Yes you can, and only shocks and springs necessary.

You can always add and change other things but not necessary.

Of course you wont have kdss

So you can just remove the AHC shocks and springs, and install Land Cruiser shocks, springs and UCA's and be good to go?

 

[grinchy]

So you can just remove the AHC shocks and springs, and install Land Cruiser shocks, springs and UCA's and be good to go?

With no front sway bar too. Though some have said this isn’t that big a deal.

Note that KDSS on the Us TLC is also an ‘active’ system, and you won’t have that either.

You do get really good fitment options for tires without kdss.

 

[turbo8]

LX upper arms and swaybars are fine to keep.

 

[trudd]

Appreciate the responses. In an attempt to put all these fragments into something a dummy like me can understand, I'm going to take a stab at a comprehensive parts list for deleting AHC and setting up stock LC suspension. For me at least, understanding the cost/effort of getting a baseline conventional suspension setup is useful to know. I like AHC and want it to last forever, but I also like to know my options.

As for ride quality and application: the goal is achieve as close to a stock LC ride as possible. Obviously there's no KDSS. This also assumes stock tire sizes, keeping the front sway bar installed, etc. If your goal is to cram more meat in the wheel well, this ain't your list.

I definitely didn't get this right the first time. Please chime in with notes and I will make adjustments to the chart. Once this gets refined, I might create a new thread for easy searching/visibility.


AHC Delete to Stock LC Suspension Parts List

Item​	OEM Part Number​	Qty	Notes
Front LH Spring	48131-60C81	1
Front RH Spring	48131-60D21	1
Front Shocks	48510-69405	2	I believe this comes with the necessary nut 94188-01401
Front Shock Support Sub-Assy	48609-60070	2
Front Shock Cushion	90948-01096	2
Front Shock Cushion Retainer	48597-60120	2
Nut for Front Shock Absorber	94188-01401	2
Bolt/Flange	90105-16088	2	Maybe this can be re-used from AHC?
Nut for Bolt/Flange	94151-21601	2	Maybe this can be re-used from AHC?
Rear LH Spring	48231-60E20	1
Rear RH Spring	48231-60F31	1
Rear Shocks	48530-69445	2
Retainer for Cushion No. 1	90948-02173	4	2 of these go on each shock
Rear Shock Cushion (No. 1 and No. 2)	90948-01064	4	2 of these go on each shock No. 1 and No. 2 cushions are the same part number
Retainer for Cushion No. 3	90948-02170	2
Retainer for Cushion No. 2	90948-02184	2
Nut Lock (top of shock)	90177-14003	2
Bolt w/ Washer (bottom of shock)	90901-19052	2

The next chart is for existing parts that can stay on the LX. I don't know much about sway bars, KDSS, UCAs, LCAs, etc. If one of these parts are viable, but not optimal, I think it's worth calling out so people can make their own judgement calls.


LX Components that work for Stock LC Setup

Item	Note
Rear Sway Bar	Example note: may want to upgrade to thicker sway bar [insert OEM part number]
Front Sway Bar	Example note: can be removed to optimize off-road travel (Is this true? I dunno)
Lower Control Arm	Same part number as LC
Upper Control Arm	Same part number as LC

Lastly, here are the partsouq schematics I referenced.

• Front Shock Schematic
• Rear Shock Schematic

Ok, fire away with feedback. Or ignore if I've totally wasted my time

 

[turbo8]

Appreciate the responses. In an attempt to put all these fragments into something a dummy like me can understand, I'm going to take a stab at a comprehensive parts list for deleting AHC and setting up stock LC suspension. For me at least, understanding the cost/effort of getting a baseline conventional suspension setup is useful to know. I like AHC and want it to last forever, but I also like to know my options.

As for ride quality and application: the goal is achieve as close to a stock LC ride as possible. Obviously there's no KDSS. This also assumes stock tire sizes, keeping the front sway bar installed, etc. If your goal is to cram more meat in the wheel well, this ain't your list.

I definitely didn't get this right the first time. Please chime in with notes and I will make adjustments to the chart. Once this gets refined, I might create a new thread for easy searching/visibility.


AHC Delete to Stock LC Suspension Parts List

Item​	OEM Part Number​	Qty	Notes
Front LH Spring	48131-60C81	1
Front RH Spring	48131-60D21	1
Front Shocks	48510-69405	2	I believe this comes with the necessary nut 94188-01401
Front Shock Support Sub-Assy	48609-60070	2
Front Shock Cushion	90948-01096	2
Front Shock Cushion Retainer	48597-60120	2
Nut for Front Shock Absorber	94188-01401	2
Bolt/Flange	90105-16088	2	Maybe this can be re-used from AHC?
Nut for Bolt/Flange	94151-21601	2	Maybe this can be re-used from AHC?
Rear LH Spring	48231-60E20	1
Rear RH Spring	48231-60F31	1
Rear Shocks	48530-69445	2
Retainer for Cushion No. 1	90948-02173	4	2 of these go on each shock
Rear Shock Cushion (No. 1 and No. 2)	90948-01064	4	2 of these go on each shock No. 1 and No. 2 cushions are the same part number
Retainer for Cushion No. 3	90948-02170	2
Retainer for Cushion No. 2	90948-02184	2
Nut Lock (top of shock)	90177-14003	2
Bolt w/ Washer (bottom of shock)	90901-19052	2

The next chart is for existing parts that can stay on the LX. I don't know much about sway bars, KDSS, UCAs, LCAs, etc. If one of these parts are viable, but not optimal, I think it's worth calling out so people can make their own judgement calls.


LX Components that work for Stock LC Setup

Item	Note
Rear Sway Bar	Example note: may want to upgrade to thicker sway bar [insert OEM part number]
Front Sway Bar	Example note: can be removed to optimize off-road travel (Is this true? I dunno)
Lower Control Arm	Same part number as LC
Upper Control Arm	Same part number as LC

Lastly, here are the partsouq schematics I referenced.

• Front Shock Schematic
• Rear Shock Schematic

View attachment 3436102
View attachment 3436103

Ok, fire away with feedback. Or ignore if I've totally wasted my time

I'll try to put this in the first post, once vetted.

Thanks!

 

[propernorf]

First post here, @turbo8 Thank you for the valuable information shared in this thread! I've just completed the AHC delete on my 2009 LX and installed the Ironman Foam Cell Pro suspension with springs and UCA. I haven't removed any relays or fuses yet, but I'm planning to do so tomorrow. After going through the thread, it seems like some users were able to retain AFS functionality without pulling the fuse or cable from the ECU. However, I'm a bit confused about whether this applies specifically to 2016+ models or if it's relevant to my 09 LX as well. Could someone clarify the steps to keep AFS for a my 2009?

Additionally, I'm wondering if I might need to keep the height sensor in place and not remove it. Any insights or guidance on this would be greatly appreciated! Thanks in advance!

I'll try to put this in the first post, once vetted.

Thanks!

 

[AJLaz]

Just ordered a Bilstein kit and some LC parts in preparation for deleting my AHC on my 2010 LX. I'll report back and to try to contribute towards a finalized conversion parts list.

 

[jbyrd78]

Just ordered a Bilstein kit and some LC parts in preparation for deleting my AHC on my 2010 LX. I'll report back and to try to contribute towards a finalized conversion parts list.

That would be awesome. I deleted the AHC on my 2004 LX470 3.5yrs ago, and I'm curious to hear if it's more complex on the LX570.

 

[AnyMal]

Appreciate the responses. In an attempt to put all these fragments into something a dummy like me can understand, I'm going to take a stab at a comprehensive parts list for deleting AHC and setting up stock LC suspension. For me at least, understanding the cost/effort of getting a baseline conventional suspension setup is useful to know. I like AHC and want it to last forever, but I also like to know my options.

As for ride quality and application: the goal is achieve as close to a stock LC ride as possible. Obviously there's no KDSS. This also assumes stock tire sizes, keeping the front sway bar installed, etc. If your goal is to cram more meat in the wheel well, this ain't your list.

I definitely didn't get this right the first time. Please chime in with notes and I will make adjustments to the chart. Once this gets refined, I might create a new thread for easy searching/visibility.


AHC Delete to Stock LC Suspension Parts List

Item​	OEM Part Number​	Qty	Notes
Front LH Spring	48131-60C81	1
Front RH Spring	48131-60D21	1
Front Shocks	48510-69405	2	I believe this comes with the necessary nut 94188-01401
Front Shock Support Sub-Assy	48609-60070	2
Front Shock Cushion	90948-01096	2
Front Shock Cushion Retainer	48597-60120	2
Nut for Front Shock Absorber	94188-01401	2
Bolt/Flange	90105-16088	2	Maybe this can be re-used from AHC?
Nut for Bolt/Flange	94151-21601	2	Maybe this can be re-used from AHC?
Rear LH Spring	48231-60E20	1
Rear RH Spring	48231-60F31	1
Rear Shocks	48530-69445	2
Retainer for Cushion No. 1	90948-02173	4	2 of these go on each shock
Rear Shock Cushion (No. 1 and No. 2)	90948-01064	4	2 of these go on each shock No. 1 and No. 2 cushions are the same part number
Retainer for Cushion No. 3	90948-02170	2
Retainer for Cushion No. 2	90948-02184	2
Nut Lock (top of shock)	90177-14003	2
Bolt w/ Washer (bottom of shock)	90901-19052	2

The next chart is for existing parts that can stay on the LX. I don't know much about sway bars, KDSS, UCAs, LCAs, etc. If one of these parts are viable, but not optimal, I think it's worth calling out so people can make their own judgement calls.


LX Components that work for Stock LC Setup

Item	Note
Rear Sway Bar	Example note: may want to upgrade to thicker sway bar [insert OEM part number]
Front Sway Bar	Example note: can be removed to optimize off-road travel (Is this true? I dunno)
Lower Control Arm	Same part number as LC
Upper Control Arm	Same part number as LC

Lastly, here are the partsouq schematics I referenced.

• Front Shock Schematic
• Rear Shock Schematic

View attachment 3436102
View attachment 3436103

Ok, fire away with feedback. Or ignore if I've totally wasted my time

I know you didn't ask but IMO totally not a good move to pull AHC unless you are putting in a high quality 3" lift / brand new suspension.
AHC is better stock for stock at most things than the LC outside of pure articulation. Keeping things stock, or stock like, its a no brainer to keep AHC instead of spending the coin on OEM parts, unless you want a perma lift.

I have around a 2-3" lift with zero mods to AHC. Just sensor changes. Then load and level adjustments to compensate, rides like factory on C load 33s.

 

[AJLaz]

I know you didn't ask but IMO totally not a good move to pull AHC unless you are putting in a high quality 3" lift / brand new suspension.
AHC is better stock for stock at most things than the LC outside of pure articulation. Keeping things stock, or stock like, its a no brainer to keep AHC instead of spending the coin on OEM parts, unless you want a perma lift.

I have around a 2-3" lift with zero mods to AHC. Just sensor changes. Then load and level adjustments to compensate, rides like factory on C load 33s.

I would agree if I had a newer, lower mileage, rust free rig, unfortunately mine is none of the above. For a fraction of the list price of an ahc pump I can have a proper suspension and never have to troubleshoot hydraulics & electronic gremlins again

 

[AnyMal]

I would agree if I had a newer, lower mileage, rust free rig, unfortunately mine is none of the above. For a fraction of the list price of an ahc pump I can have a proper suspension and never have to troubleshoot hydraulics & electronic gremlins again

Peace of mind is worth a lot, not gonna debate that.

Just remember that if any of you do the swap, your suspension will actually be worse than both the LC and LX.
You neither get the benefits of AHC nor KDSS. Just not a good move IMO and Im about to rip AHC out every other day.
I also wouldnt buy OEM because why not lift at that point but I get everyone doesnt want a lifted truck.

Not really a great option either way. If I could have bought a factory lifted LC i would have.

 

[jbyrd78]

Just remember that if any of you do the swap, your suspension will actually be worse than both the LC and LX.
You neither get the benefits of AHC nor KDSS.

If it's not too much to ask, could you explain, why it wouldn't be a smooth ride other than not having the KDSS? I thought the sway bars are beefy enough to compensate?

 

[Heckraiser]

Ride quality would be on par with a stock land cruiser. Handling would be worse due to lack of KDSS. Sway bars don't really affect ride quality in most situations (some minor exceptions), but they greatly effect body roll and handling.

BTW, if you swap over to conventional suspension and find you have too much body roll, you can always upgrade with aftermarket traditional swaybars to compensate for the lack of KDSS. It would not be as refined and versatile as KDSS, but it would be easy enough to get the handling dialed in the way you want for a primarily road-going vehicle.

 

[trudd]

Ride quality would be on par with a stock land cruiser. Handling would be worse due to lack of KDSS. Sway bars don't really affect ride quality in most situations (some minor exceptions), but they greatly effect body roll and handling.

BTW, if you swap over to conventional suspension and find you have too much body roll, you can always upgrade with aftermarket traditional swaybars to compensate for the lack of KDSS. It would not be as refined and versatile as KDSS, but it would be easy enough to get the handling dialed in the way you want for a primarily road-going vehicle.

This would be another section of the master list I want to compile - model of upgraded front/rear sway bars, required bushings, brackets(?), etc.

In my mind:

1. Minimum viable OEM LC setup
2. upgrades to OEM setup (sway bars, and anything else needed to compensate for lack of KDSS)
3. Common Aftermarket setups (shock/strut/spring components, control arm/pan hard upgrades, custom solutions like panhsrf bracket, etc).

 

[propernorf]

First post here, @turbo8 Thank you for the valuable information shared in this thread! I've just completed the AHC delete on my 2009 LX and installed the Ironman Foam Cell Pro suspension with springs and UCA. I haven't removed any relays or fuses yet, but I'm planning to do so tomorrow. After going through the thread, it seems like some users were able to retain AFS functionality without pulling the fuse or cable from the ECU. However, I'm a bit confused about whether this applies specifically to 2016+ models or if it's relevant to my 09 LX as well. Could someone clarify the steps to keep AFS for a my 2009?

Additionally, I'm wondering if I might need to keep the height sensor in place and not remove it. Any insights or guidance on this would be greatly appreciated! Thanks in advance!

So I went a head a disabled AHC on my 09 today, Here is what I did:

Here's a brief rundown of the steps I followed:

1. Disconnected the battery.
2. Pulled the AHC relay.
3. Pulled two AHC fuses on the passenger side.
4. Disconnected the two bottom cables from the AHC module behind the backseat cover and left the top one.
5. Reconnected the battery.

Everything seems to be functioning well with no errors on the dashboard. The AFS button appears to be operational, so I assume it's still functioning as intended.

Upon reading through this thread, I read that some members reinstalled the relay after disconnecting the AHC module. I'm curious to know if there's a specific reason for this and if I should also reinstall the relay in my LX.

Bonus Pic