The Lowdown on the AHC suspension? (1 Viewer)

[littleking]

Hey all,
As I indicated in a previous post...
https://forum.ih8mud.com/100-series...-lc-car-crash-thoughts-future-prevention.html

I banged up my '99 LC the other day. The insurance has totalled it out and now I am starting the search for a replacement for my baby.


Being that this post is now a few years old:

Can any LX470 owners out there comment on the longevity of the hydraulic lifting shocks/accumulators and their maintenance/replacement? Do these have the typical lifespan of shocks (30K or 60K mi), or are they designed to last 20 yrs and 300K miles? Figure that the first 5 yrs of the typical LX mall cruiser is always in the "low" position and gets nil use.

Can anyone provide any further data on their LX470 and the longevity/reliability of their AHC system and/or the shock dampning system?

There are some decent prices for a couple of LX's that I could ship back here to MA.

Final thoughts?

Thank as always,
Ryan Goodwin

 

[1loudLX]

It can go down 2" in low.

 

[2000UZJ]

it breaks

 

[1loudLX]

it breaks

and then you can do what you'd do with a LC anyways...put a lift in.

 

[2000UZJ]

and then you can do what you'd do with a LC anyways...put a lift in.

I would ditch AHC in a heartbeat. Man, we really are killing this guys hopes for a AHC rig.

 

[littleking]

I would ditch AHC in a heartbeat. Man, we really are killing this guys hopes for a AHC rig.

Hey Guys,
I appreciate it. I was leaning towards a straight LC, but there are some good deals on the LX. If I had 10 guys come back and say, "Hey I have had mine 10 years and have had no problems as long as you flush the fluid every 30k, I'd think about it.

Ryan

 

[Yukon LX]

Just keep it till it dies, then through a slee/ OME kit on for a grand and you are good to go. There are people out there with 200k on there ahc original parts right now. If you vehicle is not overloaded too, it is a comfortable riding system, and it can be nice to lift it up and down when needed.

Here are a couple threads that might help:
https://forum.ih8mud.com/100-series-cruisers/460416-who-has-most-miles-original-ahc.html

https://forum.ih8mud.com/100-series-cruisers/459272-if-you-had-choice-ahc-no.html

 

[Kigiin]

Mine still works, unfortunately!

 

[1loudLX]

Hey Guys,
I appreciate it. I was leaning towards a straight LC, but there are some good deals on the LX. If I had 10 guys come back and say, "Hey I have had mine 10 years and have had no problems as long as you flush the fluid every 30k, I'd think about it.

Ryan

if they're great deals, roll with it. You'll get nicer carpet, leather, seatbacks, proper wood trim, a nicer gauge cluster, better headlights, and if it's an older one, better HVAC controls.

 

[rrclx]

Whether one likes the ahc depends so much on personal preference. Its rides better, no doubt about it.

Reliability? It is more complicated then shocks. I drove my 06 for 40k and there were no signs at that point of any possible failure. Lexus dishes out plenty of 100k CPOs so they must be fairly confident.They have buit it for 10 years. Other car makers have had hydraulic supensions much longer then that. Just never open the fluid reservoir unless you have a really good reason to and hope for the best. Only let Lexus touch the ahc. If you want the cheapest then buy coils or convert when it fails. I love the ride of the AHC and have started an investment account to fund the replacement accus maybe 5 years down the road...IF needed.

 

[Kigiin]

and if it's an older one, better HVAC controls.

Why is that?

 

[1loudLX]

Why is that?

our HVAC controls are WAYYYYYYY cooler looking than the LC ones. The newer trucks, they all suck One day I'll have to deal with it 24/7, for now only on vacation

 

[hoser]

if they're great deals, roll with it. You'll get nicer carpet, leather, seatbacks, proper wood trim, a nicer gauge cluster, better headlights, and if it's an older one, better HVAC controls.

... memory seats, homelink, auto-dim mirrors, retractable mirrors, etc...

 

[1loudLX]

i didnt want to make it seam like the LX was that much better off the bat

 

[Brock]

actually I like my AHC....it does very good job for what it is intended...even offroad. It just cant handle the heavy front and rear bumpers with the 12k lb winch up front.

but now going to Ironman Offroad suspension....

 

[lexi4darin]

AHC isn't inherently bad. It's more complicated than normal springs, shocks, and struts but the ride quality is nicer too. Also there's some value with the ability to raise/lower vehicle.

If you've got a truck with a properly maintained AHC system, there's no reason it doesn't last for a long time.

 

[1loudLX]

AHC is perfect for a stock truck, and it's staying in my stock truck until it's no longer stock. AHC didnt like all the weight on the not so stock truck, so I removed it.

 

[tabraha]

AHC doesn't give up much to the stock suspension other than the fact it will not go 300k (most likely). Of course the conventional shocks won't either without sagging/crapping out but they're cheap (same thing for springs and t-bars). Any big armor mods and either route will need upgrading IMO.

200k on mine and it can still ride softer or firmer than a LC suspension, at my choice. It will still level a load that the regular suspension would be lights in the sky with and like other's said if it were to crap out tomorrow I'd Slee/OME it and keep on truckin.

That last statement is the key with AHC. You HAVE to be ok with knowing up front that whenever it craps out you need to go to a conventional suspension. From what I've seen the success rate with repairing accumulators/contamination is low.

I would say 150k is a reasonable longevity expectation from what I've read about others changing out accumulators etc but you never know. I won't waste my money trying and just go straight to a 2.5" lift kit most likely.

I certainly wouldn't avoid an AHC-based 100 if the $ is right.

 

[DallasCrzr]

I bought a prefectly maintained (Every 5k into the dealer for Scheduled service according to lexus records) all the way to 110k. Acording to records had no AHC problems and had flushed it at the 60k service like youre supposed to.

Like you I found a lot more good deals on LX's probably because they outsell the LC overall and especially around here in Dallas i see 1 LC for ever 6 LX even though the actual ratio was much closer.

I think the luxury features of the Lx and to me better looks (love those GLASS headlight covers) are worth buying it for.

Also it didnt look like youre old car was modded. Of course everyone here (including me) would tell you to get a lc or rip out the ahc and figure out a way to put a 20" lift with 40" tires on it BUT if youre using it as a cruiser and only light off roading to go fishing and not going to put a heavy bumper and winch then go with the AHC. Its perfectly capable of doing what 98% of people do in these cars and its really nice to have.

I have it and if you maintain it at 60 and 120k i think it could last to 200k... Initially i regretted the ahc but now i know when i put a lift on here im going to miss ahc. I tried to keep it on sport all the time but comfort stting is so comfortable. I say go lx and when/if the ahc fails in you replace it with a standard suspension for a thousand bucks....or buy my old ahc parts and fix your ahc

 

[Tinkerer]

... memory seats, homelink, auto-dim mirrors, retractable mirrors, etc...

My own 99 LX experience with such LX-unique interior/etc items:

Outside Rearview Mirrors stopped auto-down-up backup function long ago. Then the right side lost up-down adjustment altogether.

Auto-dimming is supposed to be all three mirrors (inside and 2 outside), but most of the time the outside mirrors don't dim. Except sometimes, one or the other, or maybe both, outside mirrors will dim - but not when the inside mirror/sensor is actually in a dim condition.

Homelink only works with old-style garage door openers that do not have rolling codes. Useless with pretty much any opener made in the last 10 years.

More:

Telescoping Steering Wheel function had a couple design changes after 99, to correct shudder. Mine had the shudder, first TSB done under warranty but the last design change & TSB was implemented after mine was out of warranty. I tried regreasing several times, finally threw in the towel and disconnected the telescoping motor. (Too much trouble to tear the whole thing down and put new version parts in to correct it, don't need telescoping function anyway.)

Six-disc Nakamichi Head Unit is the third one, had two replacements under warranty. This third unit occasionally acts goofy, I'm keeping my fingers crossed.

Regarding the AHC:

I think the ride is superior, for light loads and road use. Unfortunately, mine had gremlins that would repeatedly put it into limp mode on longer trips, and I never found the time and $$$ to exorcise them. (It probably would have required not only a pressure gage/fitting kit but also a Toyota Scan Tool, however it appears the original Toyota Scan Tool is obsolete, Toyota is now using a semi-custom ruggedized laptop rig, see Toyota’s Aftermarket Support & Scan Tool — Digital Literacy Project..) When the Accumulators starting acting like they were nearing complete failure, I decided to convert to stock LC to reduce cost and improve long term reliability.

AHC is complicated and expensive. When all is working well it is really nice IMO. But when it has gremlins, needs troubleshooting, or just needs the routine periodic Accumulator replacement, you see its drawbacks. (Time and $$$ long term.) Some folks have no problem burning $2000 for Accumulators once every 10 years, but that's just not realistic for my budget.