LX570 AHC height modifications (lift it!) (1 Viewer)

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Have just read through this whole thread, really interesting. Has anyone at this stage found a way to override or at least increase the speed at which the suspension will automatically reduce from H setting back to N?

What scenarios would this be useful? Just curious, not baiting you :)

In my experience, the height at which it drops from HI to N is usually faster than I want to go in 4-lo anyways.
 
Have just read through this whole thread, really interesting. Has anyone at this stage found a way to override or at least increase the speed at which the suspension will automatically reduce from H setting back to N?

There's no way to alter the software to change the transition speeds directly. Indirectly, you can do the sensor lift to raise every position by ~1.25" (30mm). Also indirectly, if you have larger tires, the speedo reads lower by that differerence (~10% for a 35") allowing one to go incremental faster before transitions.

One trick to maintaining a higher ride height to higher speeds is to use low range. In low range, it maintains a 2.5" (60mm) lift to 25mph (40kmh), and 1" (25mm) lift to 50mph (80kmh). Combine that with the sensor lift means 3.75" (95mm) lift to 25 mph and 2.25" (60mm) lift to 50mph. That's already way taller than the LC's run as they don't really lift higher than 3". More like 2" or less with gear and stuff.

Honestly, the fact that it lower at higher speeds is by design, and a good thing. If any of you have driven in "H" mode more aggressively in a parking lot, you'd know the suspension geometry is not stable nor ideal at that height. To be driving over 50mph off-road in terrain, with bad suspension geometries is not a satisfying experience. Also, maintaining some droop travel is really important. So the built in bracket's ability to lift 1.25" really is about the extent I would take it, otherwise driving at higher speeds in "H" mode makes for a terrible handling vehicle. I've done my fair share of bombing down desert washes here in California, chasing Raptors. I've not lifted my AHC at all with the only lift being 1" offered by my larger tires. If there were real obstacles to hit at speed, I would slow way down anyways. AHC does a great job at adjusting damping on the fly to keep things from bottoming out.

I may do the AHC suspension lift one day, but I enjoy good on-road handling and tow performance which I use a greater percentage of time. Heck, it's easy enough to do for off-roading days.

Separately, the 3.15" (80mm) extra high lift of AHC is pretty ridiculous if you think about it. Pair that with the 1.25" (30mm) sensor lift, and that becomes a 4.4" (110mm)!

Extra high, max sensor lift, and 33" tires as I have (1" lift), and that becomes a 5.4" (135mm) lift!$##@ :smokin:

Now if anyone were to ever put this together with a 35" tires, .5" body lift.... 7" (175mm) total lift! :eek:

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Now if anyone were to ever put this together with a 35" tires, .5" body lift.... 7" (175mm) total lift! :eek:

Or with 37” (36” measured) 1” body lift (anything else trimmed as necessary) 8.5”! Sounds perfect to me 👏

Now if only the wife would sign off :doh:
 
I was thumbing through the IG last month when I came across the below pic from a guy I think is on Mud - andrewpounder.
:censor: I say to myself and now I'm looking for LX570s on cargurus app. In the IG post he says he only does the sensor lift (like what's mentioned already) and then fit the 35s with some trimming and a body mount chop. This is what I want:
1921138

That's his pic not mine.
On my 2006 AHC equipped 100 series, I lifted it about 2" and kept the AHC working great. I bought the Japan4X4 spacers for the shocks. They are a simple kit between the bottom of the AHC shock and the LCA in front and rear spring mount in rear. I added the King springs (not to be confused with KINGS in the US) already mentioned and cranked the t-bars. And I adjusted the AHC sensors.
From reading here, it seems like adjusting sensors and the shock spacers is all that has been attempted. Has anyone tried a stiffer spring in the back (like the OEM LC200) instead of a spacer? Has anyone tried using shock spacers?
Shock spacer on a 100:
1921141

Again, not my pic.
 
I think 35s will go without the BMC in two situations:
  1. Narrow tire - I'm going this path, with 35x10.5r17 . . . as soon as I source some 17" rims anyhow
  2. Adjustable upper control arms. This will require transferring the AHC sensor lever components over to the new control arm. I was looking at the SPC arms, it seems they might have existing mounting point for this, but it could also be an ABS sensor wire or external shock mount instead. Since the LCs can fit 35s with adjustable UCAs only, it should work (even better, no KDSS) for LXs.
In the grand scheme of things a BMC isn't that big a modification, it's just not bolt on. I got a little hobby welder for christmas and it may be one of my spring projects.
 
I talked with an FJ Cruiser guy who had a bmc done on his rig for $200 at 4 Wheel Parts Wholesalers. He said it's a pretty common mod.
 
I think 35s will go without the BMC in two situations:
  1. Narrow tire - I'm going this path, with 35x10.5r17 . . . as soon as I source some 17" rims anyhow
  2. Adjustable upper control arms. This will require transferring the AHC sensor lever components over to the new control arm. I was looking at the SPC arms, it seems they might have existing mounting point for this, but it could also be an ABS sensor wire or external shock mount instead. Since the LCs can fit 35s with adjustable UCAs only, it should work (even better, no KDSS) for LXs.
In the grand scheme of things a BMC isn't that big a modification, it's just not bolt on. I got a little hobby welder for christmas and it may be one of my spring projects.

I believe this is a legitimate and doable strategy to 35s.

Some considerations of UCA vs BMC:

1) UCA's are a requirement on LC's as a result of static lift over 2" for alignment. As we have the advantage of AHC where our max lift isn't defined by large static lifts. With sensor lifts of < 2", LX's don't need UCA for alignment. The UCA then would strictly be for the benefit of clearance to the rear body mount. Is that worth adding troublesome UCA's that require regular maintenance and make noise? Long term durability is a question too. Seems to me like the more expensive and troublesome path, over a chop?

2) It's been identified that shifting the wheel too far forward with UCA's will result in CV's grenading on extreme articulation. I suspect that even short of that threshold, shifting the wheel forward via UCA's will put additional stress upon the CV, as the stroke geometry is modified from stock which is validated and likely optimal.

3) Most every Toyota truck platform that does huge tires, utilize body mount chops (BMC). This includes Tundras, FJs, 4Runners, GXs. Makes you wonder why the 200-series forum doesn't utilize this strategy more? My opinion, but suspension alignment and geometry takes precedence when fouling other things. I have moved intercoolers, turbo plumbing, and coilovers in my vehicles over compromising suspension geometry.
 
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I believe this is a legitimate and doable strategy to 35s.

Some considerations of UCA vs BMC:

1) UCA's are a requirement on LC's as a result of static lift over 2" for alignment. As we have the advantage of AHC where our max lift isn't defined by large static lifts. With sensor lifts of < 2", LX's don't need UCA for alignment. The UCA then would strictly be for the benefit of clearance to the rear body mount. Is that worth adding troublesome UCA's that require regular maintenance and make noise? Long term durability is a question too. Seems to me like the more expensive and troublesome path, over a chop?

2) It's been identified that shifting the wheel too far forward with UCA's will result in CV's grenading on extreme articulation. I highly suspect that even short of that threshold, shifting the wheel forward via UCA's will put additional stress upon the CV, as the stroke geometry is modified from stock which is validated and likely optimal.

3) Most every Toyota truck platform that does huge tires, utilize body mount chops (BMC). This includes Tundras, FJs, 4Runners, GXs. Makes you wonder why the 200-series forum doesn't utilize this strategy more? My opinion, but suspension alignment and geometry takes precedence when fouling other things. I have moved intercoolers, turbo plumbing, and coilovers in my vehicles over compromising suspension geometry.

Paul you have me curious. Looking at my rig I can’t see benefit of BMC. From my POV, the tab that holds the rocker panel on seems like it would be more invasive than the BM:

QrsDpyV.jpg


The tab isn’t shown here but is what holds the rocker in place
 
Yep ucas just to move the tire forward a bit.

My path is pizza cutters and failing that, bmc.

UCA cost the most (excluding time) and probably have the most downsides
 
Paul you have me curious. Looking at my rig I can’t see benefit of BMC. From my POV, the tab that holds the rocker panel on seems like it would be more invasive than the BM:

The tab isn’t shown here but is what holds the rocker in place

Looking up at the underside of the step - this one right? Yeah, I've adjusted it for clearance against my 33x12.5s. It will definitely need to be cut or massaged more with a 35x12.5. Minor thing IMO. @grinchy might be able to avoid it with pizza cutters and high offset wheels.

From this thread: Modifying Splash Gaurds for 33's
1921281
 
Looking for a 30 or 25 offset wheel. Am hopeful the current group buy in 25 offset steelies comes thru. If not it's probably sourcing a set of these:
And adding a 25 or 30 mm spacer
4261160A61


1921288
1921288
 
I believe this is a legitimate and doable strategy to 35s.

Some considerations of UCA vs BMC:

1) UCA's are a requirement on LC's as a result of static lift over 2" for alignment. As we have the advantage of AHC where our max lift isn't defined by large static lifts. With sensor lifts of < 2", LX's don't need UCA for alignment. The UCA then would strictly be for the benefit of clearance to the rear body mount. Is that worth adding troublesome UCA's that require regular maintenance and make noise? Long term durability is a question too. Seems to me like the more expensive and troublesome path, over a chop?

2) It's been identified that shifting the wheel too far forward with UCA's will result in CV's grenading on extreme articulation. I suspect that even short of that threshold, shifting the wheel forward via UCA's will put additional stress upon the CV, as the stroke geometry is modified from stock which is validated and likely optimal.

3) Most every Toyota truck platform that does huge tires, utilize body mount chops (BMC). This includes Tundras, FJs, 4Runners, GXs. Makes you wonder why the 200-series forum doesn't utilize this strategy more? My opinion, but suspension alignment and geometry takes precedence when fouling other things. I have moved intercoolers, turbo plumbing, and coilovers in my vehicles over compromising suspension geometry.

My answer to #3 is the limited sales numbers and initial vehicle cost prevents a lot of people/companies from aiming for our platform as a good investment from a business perspective, at least for more “extreme” solutions. Obviously, many have made a good living offering parts, but many of the parts are a different path to about the same lift and tire size.

I agree that maintaining proper geometry is very important but there are probably a lot of possibilities for fitting larger tires that can maintain proper geometry, but it will require cutting and body lifts. Most seem opposed to one or both of these.

I would look at Canguro’s rig to reverse engineer back to the size of tire you’re aiming for, but they have both 3” body lift and cut fenders to race w/ 37’s.

I’m personally very interested if we could properly weld the AHC bracket onto an aftermarket UCA, or possibly a Tundra UCA?!
 
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I was thumbing through the IG last month when I came across the below pic from a guy I think is on Mud - andrewpounder.
:censor: I say to myself and now I'm looking for LX570s on cargurus app. In the IG post he says he only does the sensor lift (like what's mentioned already) and then fit the 35s with some trimming and a body mount chop. This is what I want:
View attachment 1921138
That's his pic not mine.
On my 2006 AHC equipped 100 series, I lifted it about 2" and kept the AHC working great. I bought the Japan4X4 spacers for the shocks. They are a simple kit between the bottom of the AHC shock and the LCA in front and rear spring mount in rear. I added the King springs (not to be confused with KINGS in the US) already mentioned and cranked the t-bars. And I adjusted the AHC sensors.
From reading here, it seems like adjusting sensors and the shock spacers is all that has been attempted. Has anyone tried a stiffer spring in the back (like the OEM LC200) instead of a spacer? Has anyone tried using shock spacers?
Shock spacer on a 100:
View attachment 1921141
Again, not my pic.

He posted the pics but not much detail
200 series picture thread
 
The little tab is on the correct side and in correct location? Or am I reversed? I still think ucas are the last option to try
1921321
 
Does anyone think that the longer lengths of the already tested Tundra conversion would create too much leverage for the pressure of the AHC to still function properly with longevity?
 
Does anyone think that the longer lengths of the already tested Tundra conversion would create too much leverage for the pressure of the AHC to still function properly with longevity?

Sounds like a good time to add a secondary shock system to increase dampening and take some of the load off the AHC! I think valving of the secondary shock to work with the constantly changing rates of AHC may be a challenge though? Maybe, maybe not?
 

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