Can someone explain to me why people get aftermarket suspension and lift when a well functioning AHC system can raise the car by 3 (?) inches?

[Travis Bickle]

My main reason: the AHC system has a many components, motors, lines, fluid, ECUs, etc. If any one of those parts fails on me when I am in a remote place, i'm screwed. I ditched mine and haven't looked back.

I also sold off the old AHC parts off my truck and actually made back almost all of the money spent on the new suspension

I feel like you could say that about a 100 series in general.

 

[timmbuck2]

awesome info guys! My 100 doesn't have AHC but my "new" LX570 does. I was hoping I could maintain it and use it for minor trails. The 100 is the trail rig anyway. As always, MUD rocks.

 

[suprarx7nut]

Rear springs only?! This is music to my ears, but probably not my wife.

What alum skids/bumpers are you using? I'm leaning towards light mods and maybe selling my '03 and '04 4Runners at some point as I don't need four 2UZFEs in my life.
That plastic "engine cover" has got to go first, then maybe low profile sliders.

Yup rear springs (and spacers) are the only purchases needed for my setup.

Dissent front and rear bumpers and skids. Slee Slider steps. Love it all!

My main reason: the AHC system has a many components, motors, lines, fluid, ECUs, etc. If any one of those parts fails on me when I am in a remote place, i'm screwed. I ditched mine and haven't looked back.

I also sold off the old AHC parts off my truck and actually made back almost all of the money spent on the new suspension

I think that's a fair concern, but it needs to be put in perspective based on likelihood of failure.

Your car is full of all that complex stuff either way. Simplicity =/= reliability. The instances of unexpected failures of AHC on a trail where the system was pressure adjusted and not rotting with rust is very few and far between. Far more people have CVs fail, lower A arm torsion mounts fail, brake boosters fail, starters fail, coil packs fail, etc... The list of potential failure points is pretty long no matter what. AHC increases that list, but the overall likelihood of failure is only increased by a tiny amount and it adds back an otherwise unattainable mix of off road ability and on road comfort. Depends on your priorities, but for myself that on road comfort is a huge win for overall enjoyment of ownership.

I think for the most extreme adventurers it makes sense to go conventional, but that's a really small sliver of the crowd here. And I suspect almost all of them live in South America, Australia and Africa.

 

[Manhattan]

Correct me if I'm wrong (uh oh - that ignorance thing)... but the camber in an AHC system is not static, e.g. you have to select at which position you're going to perform the alignment. So, if you have the truck aligned in the lowest position, when raised to the highest, the camber is now off. If one likes the look of the truck in the 2"-3" "lifted" position and wants it to just stay there, the AHC override would accomplish this... but then the alignment would need to be set at that height? Right?

This is all academic for me - my 2006 came without AHC.

 

[hickuptruck]

I deleted my AHC for a Radflo 2.5" RR system which is some of the nicest you can get. I miss my AHC 75% of the time.

Why I did it?
I had just went over my AHC system with TIS 2 weeks prior and everything was up to spec. Not too far from home 2 weeks later, my rear completely sagged. Turned out to be a busted rear sensor. It would either be in AHC high in the rear, or full sag, and I was on bumpstops in the rear. I was kind of pissed a sensor would throw the suspension into full sag on bumpstops. This could have happened anywhere.

I ripped out my AHC. My highway and turning feel on the body feels far superior, and my control over bumpy and larger washboard stuff is better. I can bomb down washboards at 35-50mph for hours easily whereas my AHC i'd go half the speed and still overheat the system. I have a insanely stiff ride though, at the cost of better handling, bump control, and heat management. I have a 5x more NVH running non-AHC on performance shocks because I have stiffer torsion bar, polyurethane bushes in the shocks, and a spherical bearing compared to AHC which is all rubber bushings. I feel every imperfection on a paved road whereas the AHC floats.

Its all you gain some, and give up some.

 

[dealmaker]

I deleted my AHC for a Radflo 2.5" RR system which is some of the nicest you can get. I miss my AHC 75% of the time.

Why I did it?
I had just went over my AHC system with TIS 2 weeks prior and everything was up to spec. Not too far from home 2 weeks later, my rear completely sagged. Turned out to be a busted rear sensor. It would either be in AHC high in the rear, or full sag, and I was on bumpstops in the rear. I was kind of pissed a sensor would throw the suspension into full sag on bumpstops. This could have happened anywhere.

I ripped out my AHC. My highway and turning feel on the body feels far superior, and my control over bumpy and larger washboard stuff is better. I can bomb down washboards at 35-50mph for hours easily whereas my AHC i'd go half the speed and still overheat the system. I have a insanely stiff ride though, at the cost of better handling, bump control, and heat management. I have a 5x more NVH running non-AHC on performance shocks because I have stiffer torsion bar, polyurethane bushes in the shocks, and a spherical bearing compared to AHC which is all rubber bushings. I feel every imperfection on a paved road whereas the AHC floats.

Its all you gain some, and give up some.

When you did that with AHC ("bomb down washboards at 35-50mph for hours easily whereas my AHC i'd go half the speed and still overheat the system"), was that aired down, or full tire pressure? With my built 4Runner I'm usually air downed to 20-ish whenever I'm off road/washboard, and usually going 35mph or slower. Haven't had our LX offroad much since we've owned it, mostly beach sand a a few hundred yards of fire road or dry river bed..

 

[suprarx7nut]

Correct me if I'm wrong (uh oh - that ignorance thing)... but the camber in an AHC system is not static, e.g. you have to select at which position you're going to perform the alignment. So, if you have the truck aligned in the lowest position, when raised to the highest, the camber is now off. If one likes the look of the truck in the 2"-3" "lifted" position and wants it to just stay there, the AHC override would accomplish this... but then the alignment would need to be set at that height? Right?

This is all academic for me - my 2006 came without AHC.

Well yeah, the suspension doesn't adjust camber on the fly.

But here's the thing - that doesn't matter. You should only have it in high while trail driving where you need it. I run most all my trails in N, only raising to H when there's a section with larger rocks or obstacles.

The AHC override is a mis-adventure, IMO. There's no point to have that extra clearance above 20mph unless you're doing some Baja race driving in which case you're well outside the scope of AHC or any of the common static lifts.

Skip the AHC override and the camber thing is a non-issue. Slightly off camber under 20mph on a dirt road isn't something you're going to notice.

 

[OklahomaOvrland]

I cannot speak for anyone else. I deleted my functional AHC for one reason. A single sensor failure dropped me to my bump stops halfway down the Moki Dugway in Utah. That is a long way from anywhere. I ended up spending 2 nights in a Flagstaff hotel waiting on the part. When I got home, the AHC had to go. Yes the AHC system did ride better. But this suspension is not going to cost me days of vacation time.

 

[hickuptruck]

When you did that with AHC ("bomb down washboards at 35-50mph for hours easily whereas my AHC i'd go half the speed and still overheat the system"), was that aired down, or full tire pressure? With my built 4Runner I'm usually air downed to 20-ish whenever I'm off road/washboard, and usually going 35mph or slower. Haven't had our LX offroad much since we've owned it, mostly beach sand a a few hundred yards of fire road or dry river bed..

Sure did air down to 22psi in both instances of ahc and non ahc. I can hit larger washouts slowing down in the radflo whereas I'd hit a bumpstop pretty hard on the ahc.

 

[steeznutz]

Most lifts I see on here and facebook are like 2-3 inches on 100 series land cruisers, and if AHC can provide that along with giving a very comfortable ride, what is the rationale to switch over to aftermarket suspension? I'm a total noob here, so just wanted to get your guys' perspective. is it just more "rugged"?

I recently acquired a 2006 LX470 with AHC. The system works (goes up & down (slowly) and is level), but the ride is bouncy, especially for anyone sitting in the back. I had it checked out at a shop and they recommended removing the system as it would be more expensive to maintain the AHC over the longer term. I'm a complete greenhorn here, so I'm open to suggestions for how to smooth out the ride and keep the AHC longer-term.

 

[medtro]

Most lifts I see on here and facebook are like 2-3 inches on 100 series land cruisers, and if AHC can provide that along with giving a very comfortable ride, what is the rationale to switch over to aftermarket suspension? I'm a total noob here, so just wanted to get your guys' perspective. is it just more "rugged"?

Keeping AHC is a DIY option. Most shops will want to convert to traditional suspension system.

 

[Manhattan]

...You should only have it in high while trail driving where you need it...

See that's where all this goes wrong - "need"

Seriously though, there is an aesthetic aspect to this stuff too. We all like to think that these trucks, builds, etc. are 100% form following function. But, we (I'll admit it) like the look too. I like the stance of the 2.5" lift... and the 33s and the roof rack and the winch bumper, etc.

I have a friend who used to run a high-end bike shop. I'd walk in and say "I need... ". He'd interrupt and say "Mark, I don't sell anything you need. What do you want?" Nine times out of 10 he was right.

 

[hoser]

If you have moderate weight, I'd recommend both non-AHC torsion bars and non-AHC rear springs, set to 2" of lift (AHC pressure in spec). In the event of AHC failure, your non-AHC springs and t-bars should allow you to limp home without riding on the bump stops.

 

[JunkCrzr89]

I had it checked out at a shop and they recommended removing the system as it would be more expensive to maintain the AHC over the longer term

That’s because they don’t understand the system nor do they want to try to understand it. Most shops will give you the same answer. It’s generally the wrong answer.

 

[suprarx7nut]

I recently acquired a 2006 LX470 with AHC. The system works (goes up & down (slowly) and is level), but the ride is bouncy, especially for anyone sitting in the back. I had it checked out at a shop and they recommended removing the system as it would be more expensive to maintain the AHC over the longer term. I'm a complete greenhorn here, so I'm open to suggestions for how to smooth out the ride and keep the AHC longer-term.

If I could translate that for you, what the shop meant to say was, "we don't understand that system, but we do sell lift kits. Let us show you your lift options."

Check your pressures and check your globe health.

 

[rc50cal]

I'm a big believer in AHC now. Most of the driving most of us do is on road, even if we're simply driving to the trails. A functioning AHC system is vastly superior to a 2-2.5" conventional lift on road. There's additional maintenance, but an entirely new conventional system is not cheap either. AHC is not a problematic air system like you'd get on a Land Rover or Mercedes. Owning one of those is PAINFUL.

I have had my AHC drop to low when the truck was loaded with 7 people, plus luggage, and gear. I will probably add Kings springs (for AHC vehicles) to the back.

 

[newbielx470]

I'm a big believer in AHC now. Most of the driving most of us do is on road, even if we're simply driving to the trails. A functioning AHC system is vastly superior to a 2-2.5" conventional lift on road. There's additional maintenance, but an entirely new conventional system is not cheap either. AHC is not a problematic air system like you'd get on a Land Rover or Mercedes. Owning one of those is PAINFUL.

I have had my AHC drop to low when the truck was loaded with 7 people, plus luggage, and gear. I will probably add Kings springs (for AHC vehicles) to the back.

Totally. The reputation of any height control system is tarnished by the crappy ones from Range Rover/Mercedes Many drivers had horror stories about spending $10k+ to fix those systems every time they break.

AHC is probably good enough for the majority of Mudders. There is a similar debate on ATRAC, which is also good enough for most of us. Actually in snow, ATRAC is preferred compared to lockers.

 

[suprarx7nut]

I cannot speak for anyone else. I deleted my functional AHC for one reason. A single sensor failure dropped me to my bump stops halfway down the Moki Dugway in Utah. That is a long way from anywhere. I ended up spending 2 nights in a Flagstaff hotel waiting on the part. When I got home, the AHC had to go. Yes the AHC system did ride better. But this suspension is not going to cost me days of vacation time.

That's a frustrating experience for sure. The sensors are a potential "fail without warning" component, but thankfully are easy to carry spares. A back up sensor on board addresses it 100% and is a real quick trail changeout. You can get good used sensors for free from folks that have removed AHC. Worst case, you could proactively buy all 3 sensors brand new from Toyota for a fraction of the cost and labor of a conventional swap.

That's a good failure to be aware of, but it's also one of the most easily mitigated.

 

[Joe422]

My mistake at the time: Listening to Texasoil tell me his accumulators were better than factory accumulators. Gave him about $1.5K over time on replacements for replacements. Finally, I fussed him out and threw in the towel and threw away a bucket of blue accumulators.

Nobody knew back then what they know now. If they did (around 2007), they kept it a secret, lol

I've been conventional for a long time, but nothing can replace the buttery smooth ride of a functioning AHC.

I have 2 cans of unopened fluid if anyone needs them...

Ahh yes... TexasOil... I fell for his gimmick trash recharged accumlators at one point too... back when OE ones were $2k/set.
Later had to buy new OE globes again... And spot on about the lack of real info back then.

After throwing over $5k+ in parts alone trying to keep AHC working well over the years (17 yrs ownership) ... multiple sets of accumulators, countless cans of fluid, rebuilding AHC motor, replacing all 4 shocks ... (and LX was 100% bone stock that entire time), it would only be fixed for a couple yrs at a time, before something else went bad on the AHC. Simpy put, it was giving us more stress, and got very annoying every couple yrs.. Swapping to LX100 susp w/ Airlift airbags, and Whiteline HD sway bars was a cheap, simple, and reliable solution that worked well.

Later swapped to Ironman lift kit for the load and lift. Quite happy with the ride quality overall, and off road performance.

Even with the info available now... I'm happy with the simplicity of the non-AHC setup.
Dont get me wrong, I know how nice AHC is... I fell in love with it since we drove it off the dealer lot. Its incredible... but throwing so much cash at it only to have it need service/repair every few yrs... the honeymoon is over. In this case, for me, simple is better.

***Btw, the AHC Switch delete, pocket cubby is great~ haha

 

[kreiten]

I run the OME medium springs in the rear to help with the weight of the rear bumper and will proly swap out the torsion bars for the LC ones once I add a front bumper. I also added the Wheeler front bump stops to the front, if AHC were to take a s*** on the trail the OME rear springs and front bump stops would in theory get me off the trail... System works great for me, I drive to the trail in regular mode and then crank it to high when I slap the B in 4Low...