What prevents AHC removal?

[OregonLC]

I've seen a number of posts about the robustness of the 200 AHC system. Good to see that it's living up to Toyota quality. Weight capacity and ability to add sliders, however, seems to be the sticking point for me should I add an LX to the fleet. While it seems that there may be upcoming offerings for sliders, I still don't see myself living with a 1,400 payload capacity.

Other than it being a lot of work, is there anything that would physically prevent replacing the AHC with something like Slee's Heavy Lift kit with BP-51's? Is roll control tolerable (and safe) without the AHC system augmenting cornering stability?

Just trying to plan out what might be next in the stable. Many more LX's out there to pick through than LC's...

 

[SWUtah]

It's been a few years since I researched this but they have armored up LX570's that have had their AVS/AHC systems enhanced to carry the added weight of a armored vehicle. From what I read on the armored vehicle site it was not a big change to increase the capacity.

 

[OregonLC]

It's been a few years since I researched this but they have armored up LX570's that have had their AVS/AHC systems enhanced to carry the added weight of a armored vehicle. From what I read on the armored vehicle site it was not a big change to increase the capacity.

From what I could find, there's the Nestle option that 4x4Tripping used:
Equipment Land Cruiser V8: OFFROAD-NESTLE
Beefed up AHC Components

It might be a good solution, might not. Seems like it worked well for them. The trouble is you'd be pretty deep into your investment before you figured out how well it worked. BP-51's (or equiv) are pretty well vetted out in the market and keep things simple. If I knew that stripping the system out and going 'old school' was a viable option then I'd be more inclined to try. That's the question I'm trying to sort out. I've posted before in the 100 forum that I really enjoy the AHC on our 2004 LX mall cruiser and that if I were ever to wheel one I'd enjoy riding the AHC hard until it broke. But with the 100, it's an easy change to conventional hardware. With the Nestle struts there's still the additional pressure load on the AHC pumps and valving. Perhaps that's a non-issue in the 200 world.

What would be a deal killer is no bolt-on sliders for the 200 LX. I have read posts where they may be on the horizon. Again, knowing there was an option to yank the AHC bits and go old school would buy me the comfort of knowing that I had options available.

 

[TonyP]

I've seen a number of posts about the robustness of the 200 AHC system. Good to see that it's living up to Toyota quality. Weight capacity and ability to add sliders, however, seems to be the sticking point for me should I add an LX to the fleet. While it seems that there may be upcoming offerings for sliders, I still don't see myself living with a 1,400 payload capacity.

Other than it being a lot of work, is there anything that would physically prevent replacing the AHC with something like Slee's Heavy Lift kit with BP-51's? Is roll control tolerable (and safe) without the AHC system augmenting cornering stability?

Just trying to plan out what might be next in the stable. Many more LX's out there to pick through than LC's...

Physically? Probably pretty straightforward. Electrically? Probably a nightmare. Also you'd be a step below a usdm LC since you'd not have kdss, just basic bars. I suppose it's possible to add it on. I've heard of such things in the 4Runner community.

 

[OregonLC]

What electrically would be a nightmare? With the 100 it's just a matter of disconnecting the harness and yarding out the equipment and plumbing. Very commonly done, in fact I'd say the majority of the LX's on the 100 forum have done it. Is it more integrated in the 200's electronics?

Yes, you'd be sans KDSS, however with a soft antisway bar I'm not sure how much you'd give up as far as articulation goes. OTOH, I do wonder how it would behave on the highway.

 

[kreiten]

From what I could find, there's the Nestle option that 4x4Tripping used:
Equipment Land Cruiser V8: OFFROAD-NESTLE
Beefed up AHC Components

It might be a good solution, might not. Seems like it worked well for them. The trouble is you'd be pretty deep into your investment before you figured out how well it worked. BP-51's (or equiv) are pretty well vetted out in the market and keep things simple. If I knew that stripping the system out and going 'old school' was a viable option then I'd be more inclined to try. That's the question I'm trying to sort out. I've posted before in the 100 forum that I really enjoy the AHC on our 2004 LX mall cruiser and that if I were ever to wheel one I'd enjoy riding the AHC hard until it broke. But with the 100, it's an easy change to conventional hardware. With the Nestle struts there's still the additional pressure load on the AHC pumps and valving. Perhaps that's a non-issue in the 200 world.

What would be a deal killer is no bolt-on sliders for the 200 LX. I have read posts where they may be on the horizon. Again, knowing there was an option to yank the AHC bits and go old school would buy me the comfort of knowing that I had options available.

@richxd87 Has the Slee Sliders on his LX570, I saw them in Breck, look super nice!

 

[OregonLC]

@richxd87 Has the Slee Sliders on his LX570, I saw them in Breck, look super nice!

Right on. Any link to pics? IMO sliders it the first and most critical add to any overland/trail rig.

 

[TonyP]

What electrically would be a nightmare? With the 100 it's just a matter of disconnecting the harness and yarding out the equipment and plumbing. Very commonly done, in fact I'd say the majority of the LX's on the 100 forum have done it. Is it more integrated in the 200's electronics?

Yes, you'd be sans KDSS, however with a soft antisway bar I'm not sure how much you'd give up as far as articulation goes. OTOH, I do wonder how it would behave on the highway.

From what I understand, it's significantly more integrated than a 100.

So you're saying a soft anti-sway is the same as KDSS?

 

[OregonLC]

From what I understand, it's significantly more integrated than a 100.

I guess that's my question. Will it take out other systems? My only reference is the 100. On that model, aside from dash lights, it's virtually a stand-alone system. Even the controller module can be replaced with a factory pocket to hold your cell phone.

So you're saying a soft anti-sway is the same as KDSS?

Not the same at all, but a light anti-sway would have the benefits of greater articulation and better ride on washboards than a properly sized anti-sway. 100 drivers have experimented with disconnect front ASBs with good success on the trail, albeit objectionable road manners. Not trying to downplay the KDSS system at all, just trying to vet out how one could take an LX and mod it into a simply mechanical suspension.

 

[GordJ]

The little bit of research that I did showed the main disadvantage to the Slee sliders is the removal of the existing rocker panels and installation of new LC panels. I think it'll add about $750 to the bill. The panels are cheaper than I thought and removal and install is a small job. If it wasn't for the need to swap panels I would be styling with the Slees right now.

 

[SWUtah]

Member on Club Lexus did a 10k mile trip through Africa in a diesel 200 with AHC/AVS, he added upgraded (bigger) armored vehicle AVS shocks and Toyota "red" springs which he stated were also used on armoured 200's with AVS/AHC. His 200 had heavy bumpers, sliders, etc. and gave him no problems going through Africa. Sounds pretty solid. I read his thread and he put his 200 through more then most LC owners would think about putting their rig through.

 

[Markuson]

The little bit of research that I did showed the main disadvantage to the Slee sliders is the removal of the existing rocker panels and installation of new LC panels. I think it'll add about $750 to the bill. The panels are cheaper than I thought and removal and install is a small job. If it wasn't for the need to swap panels I would be styling with the Slees right now.

To be clear...It's not so much that the *slee* sliders cause an issue with the panels....as much as it is the fact that the LX steps involve the panels. Any slider design built for the LX is going to be stuck dealing with this step/panel integration design that creates this issue.

 

[OregonLC]

@Markuson I see that you have lockers and 4.88s in your list of wants for your 200 LC.

Are you setting your rig up to be more of a crawler or for general overland use? I'm running 4.88s and lockers on the 100, but I've seen some vids of the 200's ATRAC in operation and it's very impressive. On the 100 lockers definitely gain capability over ATRAC alone. Just curious what the marginal gain for lockers is on the 200 vs the updated ATRAC. The other benefit on the 100 is that the ARB carrier adds stiffness and tends to reduce the risk of shedding a gear tooth due to component flex. Is this a concern on the 200's as well?

Also re: the 4.88's are you hoping to gain in lowering your low range or for improved highway control?

 

[TonyP]

Despite ATRAC being more refined in the 200, it is absolutely not a replacement for lockers. Your lines are greatly limited with ATRAC and you need to take obstacles at speed (which is dangerous) in order to keep traction. A perfect example was Mark on Red Cone having to adjust his line a few times due to cross wheel slippage. Same thing on the Golden Crack in Moab for the rest of us. ATRAC does not do well in this cross traction situation. The driver behind him had a rear locker and just rolled up the obstacle.

 

[Markuson]

@Markuson I see that you have lockers and 4.88s in your list of wants for your 200 LC.

Are you setting your rig up to be more of a crawler or for general overland use? I'm running 4.88s and lockers on the 100, but I've seen some vids of the 200's ATRAC in operation and it's very impressive. On the 100 lockers definitely gain capability over ATRAC alone. Just curious what the marginal gain for lockers is on the 200 vs the updated ATRAC. The other benefit on the 100 is that the ARB carrier adds stiffness and tends to reduce the risk of shedding a gear tooth due to component flex. Is this a concern on the 200's as well?

Also re: the 4.88's are you hoping to gain in lowering your low range or for improved highway control?

You asked what type of wheeling... For me it includes just about everything. Lots of overlanding...but also dealing with rocks in Moab or above that lsewhere. So my use is more an all-of-the-above. But whatever one's tendencies... when you need to get past a barrier...you need to get past it...and it doesn't matter what your preferred terrain is at that point. You either have the ability to beat the barrier or you might be in trouble. As a guy who is more likely to go gor it...lockers are a key capability that can be useful just about anywhere except pavement. Example... If the crazy trails that turned into a nutty late-night winch-fest happens again next year...I'll be there.

4.88's are to deal with a seriously heavy rig running 35's. To me, that's not even a question...except for the money to afford it right now. I don't like that my torque converter is getting a workout more than it was designed to get...and I want my gear shifts and engine braking to be more where it should be. Since we can't reprogram our computers for 35’s...the transmission ends up off due to essentially upshifting everything without the computer knowing (35's). Plus...I'd love to get my zippy acceleration back. This truck isn't designed for 35's and 8000lbs. 4.88's will greatly reduce the strain.

As for why lockers... ATRAC only goes so far, and can still leave hung wheels spinning. Crawl control can help, but it takes over speed. I want full control when barely making it up/over/out of barriers, steps, holes, loose dirt and large rocks. ATRAC or Crawl are really no substitute for full control over full power at all wheels. Momentum is the other thing I hate about Crawl, as it's difficult to control bursts of momentum you could otherwise use with lockers. I don't mean ramming the castle with speed...but just full control over all of it, and not wondering which wheels are gonna turn when the computer feels like turning them.

Lockers don't cure everything, but it's a major tool to have at your disposal, and I'll use it often. There have been tons of spots where I'd have locked thing up given the choice.

 

[TeCKis300]

In regards to removing AHC, I'm curious as well as to the specific integration issues. No one has offered any specifics. I'd suspect the powertrain would work fine, but perhaps it's the ancillary systems such as ABS/ATRAC/VSC/etc. that potentially would stop working.

It would be possible to test this for someone that wants to try without committing, by unplugging the various sensors and suspension subsystems/computers, to find out what effects there are.

That said, it's very possible for AHC to support more than the standard payload rating. The general strategy is to beef up the standard coil spring part of the system, to carry the bulk of the additional load. Ideally keeping the AHC spring part of the system carrying it's factory target load. This was easy on the 100-series by calibrating neutral pressures as displayed in techstream, but as I understand it, the outputted variables have changed. There were individuals that plumed a hardware pressure gauge into the AHC system to be able to dial airbags in depending on load.

Coil spacers would be an easy way to incrementally augment the system.

Airbags on the rear could carry a lot more weight, but that doesn't help the front axle.

Full replacement springs would ideal.

For someone heavy enough, one could possibly even use the standard LC springs on the LX AHC setup, and adjust the ride height up enough to balance neutral pressures. This would be something like ~50% more spring rate, which might just work well enough?

 

[TonyP]

In regards to removing AHC, I'm curious as well as to the specific integration issues. No one has offered any specifics. I'd suspect the powertrain would work fine, but perhaps it's the ancillary systems such as ABS/ATRAC/VSC/etc. that potentially would stop working.

That's my thinking too. I don't have any concrete evidence, just speculation that it'll cause issues with the sub-systems as the 200 AHC appears to be fairly more sophisticated than the AHC in the 100. It seems many of the systems are intertwined in bizarre ways in the 200. I could be wrong though.

 

[SWUtah]

Call one of the vendors that armoured up the LX570's and ask. Do a google search their are several. Let us know what you find out kind of curious myself.

 

[OregonLC]

You asked what type of wheeling... For me it includes just about everything. Lots of overlanding...but also dealing with rocks in Moab or above that lsewhere. So my use is more an all-of-the-above. But whatever one's tendencies... when you need to get past a barrier...you need to get past it...and it doesn't matter what your preferred terrain is at that point. You either have the ability to beat the barrier or you might be in trouble. As a guy who is more likely to go gor it...lockers are a key capability that can be useful just about anywhere except pavement. Example... If the crazy trails that turned into a nutty late-night winch-fest happens again next year...I'll be there...

As for why lockers... ATRAC only goes so far, and can still leave hung wheels spinning....

Lockers don't cure everything, but it's a major tool to have at your disposal, and I'll use it often. There have been tons of spots where I'd have locked thing up given the choice.

I hear you on the advantages of lockers. I currently pilot a tripple-locked 100 on 34x12s and 4.88s. Lockers will give you the best shot of rolling up something. There have been a number of times that I have rolled up things effortlessly when locked that would have definitely been 'drama' with just ATRAC. That said, my main partner in crime runs an unlocked 4th Gen 4Runner. We go all the same places. He's lighter, narrower, and I've yet to see a place where he can't get. There's been times where he's pulled winch line and there's been times when I've pulled winch line. Won't say that one vehicle is necessarily better than the other. Although I might tip my hand to him just for the pure aspect of power:weight ratio. I could certainly see myself adding lockers to a 200 build some day. Was just curious how much 'improved' the 200 ATRAC was. Some of the YouTube vids make it look really super.

4.88's are to deal with a seriously heavy rig running 35's. To me, that's not even a question...except for the money to afford it right now. I don't like that my torque converter is getting a workout more than it was designed to get...and I want my gear shifts and engine braking to be more where it should be. Since we can't reprogram our computers for 35’s...the transmission ends up off due to essentially upshifting everything without the computer knowing (35's). Plus...I'd love to get my zippy acceleration back. This truck isn't designed for 35's and 8000lbs. 4.88's will greatly reduce the strain.

Not arguing with your logic here at all. 8,000 lbs (1,200 lbs over GVWR) is a feat to accomplish. I've fought the same battle but with a 4 speed. 230 hp pulling that mass around stinks! For me the debate was between 4.88s and 5.29s. 4.88s won out because it's an easier install in the 100 (5.29s require a hybrid of parts). Conventional wisdom is to gear down as weight and tire size go up. However, I'm about to go back to 4.30's and here's why: it put me in the wrong RPM band at the speeds I need to travel. If you look at the chart below, with 4.88s I can't hold 3rd gear on a climb. My whole goal was to pull hills better and I still can't hold 3rd. But what it did was push 2nd up above 4,100 rpm. Not where I want to hang out. Had I kept the 4.30s I'd have been right in the sweet spot of the power band in 2nd at 55mph. Similarly, if I'm pulling a trailer or have a headwind, it's hard for the A343F to stay locked at 2,400 rpm in 4th at 65mph. Had I kept the 4.30s I'd be in 3rd at a comfortable 3,200 rpm and would keep the trans from hunting.

I bring this up because you may have a similar situation with the AB60F ratios. With the 3.90 in 3rd I'm guessing you can hold 55mph at 2,900 rpm. With 4.88s this pushes you to 3,600 rpm in 3rd or 2,700 rpm in 4th. The 3UR may be happy pulling at 2,700 rpm. Much bigger cajones in the 5.7. Not saying that it's a good or bad idea for your truck or your mission, just sharing what I learned. You may want to look at 4.30s as well. Some good ratios there. Not sure what your highway performance is like, but 4th with 4.30s looks like it's a better chose than 5th with 4.88s.

The other item to consider is driveline speed and vibrations. It's common in the 100 to pickup a harmonic vibration in the cab between 55 and 60 when going to 4.88s due to the increased rotational speed of the driveshaft. May or not be a prob with the 200. Just something to be aware of.

Again, please don't take this as critiquing your build plans. 4.88s may be a great way to go. Just wanted to give some real-world feedback from my experience. If I keep the 100 for a few more seasons it's going to be re-geared (again) over this coming winter, going back to stock 4.30s. I will lose performance off the line and the truck won't feel as quick at stoplights. But where it really struggles it will be geared better.

 

[OregonLC]

In regards to removing AHC, I'm curious as well as to the specific integration issues. No one has offered any specifics. I'd suspect the powertrain would work fine, but perhaps it's the ancillary systems such as ABS/ATRAC/VSC/etc. that potentially would stop working.

It would be possible to test this for someone that wants to try without committing, by unplugging the various sensors and suspension subsystems/computers, to find out what effects there are.

That said, it's very possible for AHC to support more than the standard payload rating. The general strategy is to beef up the standard coil spring part of the system, to carry the bulk of the additional load. Ideally keeping the AHC spring part of the system carrying it's factory target load. This was easy on the 100-series by calibrating neutral pressures as displayed in techstream, but as I understand it, the outputted variables have changed. There were individuals that plumed a hardware pressure gauge into the AHC system to be able to dial airbags in depending on load.

Coil spacers would be an easy way to incrementally augment the system.

Airbags on the rear could carry a lot more weight, but that doesn't help the front axle.

Full replacement springs would ideal.

For someone heavy enough, one could possibly even use the standard LC springs on the LX AHC setup, and adjust the ride height up enough to balance neutral pressures. This would be something like ~50% more spring rate, which might just work well enough?

The think I like about springs is they don't cause an increase in AHC pressures. And perhaps the Nestle shocks don't either if their diameter increases. I'm of the camp that the less strain on the system the better.

Pulling the AHC fuse should be a quick way to find out how 'integrated' it is. If you get a bunch of orange lights on the dash then it's probably not a happy truck.