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? (1 Viewer)

[ed94r]

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

LOL. We went through the same exact experience. It would ride good for a few weeks/a month, then the telltale bounce. I was sooo tired of strap wrenches and being soaked in fluid. I replaced so many accums. that a friend made me a wrench out of flat iron for the job.

No mas.

 

[David*BJ70]

The «maximum» weight that can be supported by a stock AHC before bottoming out is +/- 1200 pounds.

^^ base on some tests by added and removed up to 7 adults and driving around !

I personally chose to delete my AHC because of the low availability of parts and knowledge «up here» in Canada. More over, driving in very remote location far from civilization and had equipped my vehicle with bull bar, side rail and step, winch, RTT, fridge and all camping stuff and did not want to facing problems in the middle of nowhere.

Being today at 7600pounds with vehicle occupants, that was an excellent decision

 

[Manhattan]

@kreiten, for all of our benefit, please post that pic any and every time it's relevant - suspension, bumpers, tires, depth of field...
Seriously, that's the pic we all hope for when we review the scores of pics after a weekend wheeling!

 

[kreiten]

@kreiten, for all of our benefit, please post that pic any and every time it's relevant - suspension, bumpers, tires, depth of field...
Seriously, that's the pic we all hope for when we review the scores of pics after a weekend wheeling!

thanks for the props!!!

 

[kwon-offroad]

The «maximum» weight that can be supported by a stock AHC before bottoming out is +/- 1200 pounds.

^^ base on some tests by added and removed up to 7 adults and driving around !

But also entirely dependent on where you pressures are in the range.

 

[dealmaker]

I feel for you guys in the rust belt. My 15 yr old 137k LX still looks like new underneath being a So Cal car, and has been a soccer mom mall cruiser road trip machine since Day One.

I'm really stoked to learn what I'm learning in this thread about AHC. I haven't perused the subject since...oh...maybe 2013/2014 when I bought Techstream, flushed the system, and replaced the rear coils w/OEM. I love the on-road ride and the "Sport---Soft" settings switch. I'm gonna treat this system like a baby and flush it every two yrs from now on.

My only concern is hiccuptrucks comment about the system overheating on washboard. I'd like to at least think about getting the LX up to my Panamint Valley/DV playgrounds, but the overheating thing, even if aired down, is a concern, given the vast # of miles one drives on washboard up there.

 

[suprarx7nut]

But also entirely dependent on where you pressures are in the range.

Yup. And if you plan on carrying an occasional 1200 lbs of extra gear, set your pressures based on at least some of that weight. And now your max weight has been raised even further.

Easy peasy.

AHC doesn't have a hard 1200 lb limit. It has a ~1200 lb (or 900 or whatever) dynamic load range which you can configure for whatever you want.

And again, this applies to standard suspension. if you take a stock non-AHC suspension and load up 1200 lbs of gear/people, it's going to squat and ride horribly and you should be changing springs or adding air bags to accommodate that load. AHC can do far better than conventional within that massive ~1000 lb load range because it can dynamically change the net spring rate. Once you go beyond that hydraulic range that you've configured, AHC gives up and conventional has a slight advantage until you reconfigure, but within any given configuration range, AHC has superior dynamic weight carrying characteristics.

In this sense, I think AHC gets punished for doing so well within that range. It's ability to handle lots of extra weight masks the need for reconfiguration where a standard system squats right away and notifies the owner that something needs updating. AHC does better in a wider range of loads so it seems a bit unfair to fault it for the extreme scenario where it's slightly worse.

Extra 500 lbs? Perfect.
700 lbs? Fine.
1000? yup, still good, no ill effects.
1250 lbs? Out of configuration, enjoy L mode until you correct your suspension.

Those first 3 lines are a clear win in the AHC column and line 4 applies to both AHC and conventional with a slight nod to conventional.

 

[suprarx7nut]

I feel for you guys in the rust belt. My 15 yr old 137k LX still looks like new underneath being a So Cal car, and has been a soccer mom mall cruiser road trip machine since Day One.

I'm really stoked to learn what I'm learning in this thread about AHC. I haven't perused the subject since...oh...maybe 2013/2014 when I bought Techstream, flushed the system, and replaced the rear coils w/OEM. I love the on-road ride and the "Sport---Soft" settings switch. I'm gonna treat this system like a baby and flush it every two yrs from now on.

My only concern is hiccuptrucks comment about the system overheating on washboard. I'd like to at least think about getting the LX up to my Panamint Valley/DV playgrounds, but the overheating thing, even if aired down, is a concern, given the vast # of miles one drives on washboard up there.

I've done a bit of washboard driving and never noticed issues. Did about 10-15 minutes at a time just this last weekend with normal trail driving in between and two back to back hour long stints behind the Tetons last year. If anything was overheating I couldn't notice it and the system has happy in N.

 

[Kabanstva]

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.

Same. Got tired of wondering when it will bottom out again on me. No rust 100 with a hair over 100k.

 

[steeznutz]

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.

I live in Atlanta and the shop I went to has a pretty good reputation (on this board), and the first option they quoted was for a non-lift suspension replacement (delete AHC, replace with standard LC shocks). And from what I can tell the cost of 4 new globes would be similar to a lift kit with 4 shocks, 2 springs, & 2 torsion bars (labor excluded) and both of these options are more expensive than the initial work they quoted. I like the AHC and I'm definitely re-considering the 'delete AHC/install full-time lift' option in favor of repairing the AHC, it's just that there doesn't seem to be a clear cost advantage other than getting the globes at a discount.

 

[suprarx7nut]

I live in Atlanta and the shop I went to has a pretty good reputation (on this board), and the first option they quoted was for a non-lift suspension replacement (delete AHC, replace with standard LC shocks). And from what I can tell the cost of 4 new globes would be similar to a lift kit with 4 shocks, 2 springs, & 2 torsion bars (labor excluded) and both of these options are more expensive than the initial work they quoted. I like the AHC and I'm definitely re-considering the 'delete AHC/install full-time lift' option in favor of repairing the AHC, it's just that there doesn't seem to be a clear cost advantage other than getting the globes at a discount.

I'm not sure I follow. It might help to use numbers.

Globes should be ~$750 for a full set via Impex, but could be upwards of $4,000 if you opt to donate a few grand to your local dealer owner. Labor is probably a couple billable hours. Assuming you buy from Impex/ebay or another near-wholesale source, figure $1-1,500 for a globe change out.

Lift kit and AHC delete should be $2-4k, pending what kit you get and how careful they are about the AHC removal.

What numbers are you getting from your local place?

 

[David*BJ70]

I AHC delete myself on my vehicle. Absolutely all components of the AHC have been removed.

I opted for an OME kit which cost me 1250$ (CDN$). It took me 3 days for the work in my driveway crawling under my Cruiser. I had a lot of difficulty removing the TB from the anchors and removing the rear shocks was more than painful.

 

[steeznutz]

I'm not sure I follow. It might help to use numbers.

Globes should be ~$750 for a full set via Impex, but could be upwards of $4,000 if you opt to donate a few grand to your local dealer owner. Labor is probably a couple billable hours. Assuming you buy from Impex/ebay or another near-wholesale source, figure $1-1,500 for a globe change out.

Lift kit and AHC delete should be $2-4k, pending what kit you get and how careful they are about the AHC removal.

What numbers are you getting from your local place?

About $2500 for AHC delete/Dobinsons 1-1.5" install, including labor. The original quote to delete AHC and replace with no lift, standard LC shocks was about $1200 (I think, also including labor). My very rough estimate of repairing the AHC is about $1500-2k (that's just me guessing, no quote).

 

[suprarx7nut]

About $2500 for AHC delete/Dobinsons 1-1.5" install, including labor. The original quote to delete AHC and replace with no lift, standard LC shocks was about $1200 (I think, also including labor). My very rough estimate of repairing the AHC is about $1500-2k (that's just me guessing, no quote).

Ok, thanks, that makes sense. That AHC figure sounds like a middle ground between the go-to lower priced sources and retail pricing for a globe swap. A little high, but in the ballpark at least.

 

[YvesNL]

I just replaced my AHC system with Ironman Foam Cell Pro suspension. I love the ride of the new suspension but AHC was smoother. You can't compare the the two really.
I had some sensor & wire issues, replaced those, not a big deal. Later I upgraded the rear springs to King's & fixed two rusted out lines.

AHC is great, you can easily change out the springs for more load and have a great ride.

The reason I removed my system was rust. All four lines leading to the shocks (the others also) had a lot of deep rust, one of them started leaking when I was off-roading in Poland. I had already repaired some lines by replacing small sections, they were accessible so not a problem.

Now I had to replace all four lines from Globes to the Shock, these are expensive and lot of work to change. Mostly due to the rusted bolts on top of the shocks an accessibility. Other than a lot of rusted lines I would not know why you would remove the AHC.

I could've just replaced the one broken line but the others were is such a bad condition that I couldn't do that. I like a reliable system and it was too costly in time and money to get my AHC system up to spec.

Read the FSM and familiarize yourself with the system, check neutral pressures and correct if necessary. If you worry about sensors open them up, check their condition, lube up the O-ring and close them again. Or you could find a mechanic that knows the system and ask him for help.

 

[JJ_SC]

I've done a bit of washboard driving and never noticed issues. Did about 10-15 minutes at a time just this last weekend with normal trail driving in between and two back to back hour long stints behind the Tetons last year. If anything was overheating I couldn't notice it and the system has happy in N.

Yeah, I've done A LOT of driving on washboard roads for hours at a time. Usually around 35-45 mph. There's always a sweet spot in speed where it smooths out a bit. I'm usually aired down to about 16 to 18 psi. I've never had an issue at all.

For what it's worth, a buddy of mine is an exec at a high end off road shock company. In a conversation with him about replacement shocks for the LC his comment was something to the effect of, "why in the world would you replace that AHC system? It's awesome."

 

[Ramathorn15]

Love the AHC. My truck is an absolute pig when fully loaded for trips like Mexico. Full armor, bumpers, rtt, trailer (sometimes), 16 gallons of water where the spare used to be, 14 gallons of water in tanks in the back seat area, two huskies, drawers loaded up, sometimes 5-10 gallons of extra gas, lifted ~2", etc.

It took a bit, but once I got it dialed in it's been great. I'm running stock LC springs and TB and my pressures are perfect when loaded up. It even feels great when daily driving with lots of the above mentioned stuff not in/on the truck. I'd say it drives smoother than our '17 LC.

As for washboard, we've done a ton and never had overheating issues. I've actually taken a IR thermometer to the shocks after a few hours of washboard and they were just a bit over ambient. My friends on the same trip with various shock setups were hot as hell.

AHC is king if you know what you're doing and understand the basic principles of how it works (very simple). Only reason I'd suggest to anyone to swap would be rust, but even then I'd probably still suggest fixing if budget allows.

 

[Roosevelt T]

IMO the biggest advantage to keeping AHC is that you can wax poetically about it in every AHC thread that pops up on the forum, which somehow happens about every 3 months even though there's about 180 of them if you search.

 

[ramangain]

IMO the biggest advantage to keeping AHC is that you can wax poetically about it in every AHC thread that pops up on the forum, which somehow happens about every 3 months even though there's about 180 of them if you search.

Stop being so truthful, er, silly

 

[drspace5]

Love the AHC. My truck is an absolute pig when fully loaded for trips like Mexico. Full armor, bumpers, rtt, trailer (sometimes), 16 gallons of water where the spare used to be, 14 gallons of water in tanks in the back seat area, two huskies, drawers loaded up, sometimes 5-10 gallons of extra gas, lifted ~2", etc.

It took a bit, but once I got it dialed in it's been great. I'm running stock LC springs and TB and my pressures are perfect when loaded up. It even feels great when daily driving with lots of the above mentioned stuff not in/on the truck. I'd say it drives smoother than our '17 LC.

As for washboard, we've done a ton and never had overheating issues. I've actually taken a IR thermometer to the shocks after a few hours of washboard and they were just a bit over ambient. My friends on the same trip with various shock setups were hot as hell.

AHC is king if you know what you're doing and understand the basic principles of how it works (very simple). Only reason I'd suggest to anyone to swap would be rust, but even then I'd probably still suggest fixing if budget allows.

Tough lookin rig! Looks like that is a Lexus? If so, to confirm, you are running stock Toyota LC rear springs and front torsion bars? IF that's correct, are your springs the AHC version or non-AHC?