2006 LC Shocks (1 Viewer)

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Hey guys-
I have an 06 with AHC (unfortunately) with 160k on the clock. I don't think that the previous owner ever replaced the shocks. I am thinking OEM shocks and springs if those parts are still available. Is there anything else while I'm in there that I should replace as well?
Thank you in advance.
 
I think you mean “fortunately”.

Unless the shocks (hydraulic rams) are leaking fluid they last essentially forever. You would be better served reading up on just doing some basic maintenance on the AHC system - fluid change, check globe health, etc.
 
Hey guys-
I have an 06 with AHC (unfortunately) with 160k on the clock. I don't think that the previous owner ever replaced the shocks. I am thinking OEM shocks and springs if those parts are still available. Is there anything else while I'm in there that I should replace as well?
Thank you in advance.
I’ve got 300k on my AHC and it’s fine. Flush your fluid before trashing the system.
 
Even if they are leaking a little it's likely that your AHC only needs a little maintenance. Once everything is dialed in they'll be fine.
 
I think you mean “fortunately”.

Unless the shocks (hydraulic rams) are leaking fluid they last essentially forever. You would be better served reading up on just doing some basic maintenance on the AHC system - fluid change, check globe health, etc.
I keep reading that AHC is to be avoided. I never use it. I didn't know the shocks were specific to the AHC. Thank you for letting me know. I have an 80 that is much more simple.
 
I think you mean “fortunately”.

Unless the shocks (hydraulic rams) are leaking fluid they last essentially forever. You would be better served reading up on just doing some basic maintenance on the AHC system - fluid change, check globe health, etc.
No leak. Truck just feels like the shocks are too soft and the truck is tipsy. The PO had the AHC flushed and serviced at around 120k. I guess I just don't know enough about this truck.
 
Like I said… do some research on here for how to maintain AHC. Lots of great threads.

The amount of variability between full soft and full sport on my truck is night and day. Full soft is like a 60s Cadillac and full sport is like tuned coils on a German car. Obviously this is still a Lexus, but you should be able to notice a change in how it rides when you adjust settings.

My guess is you need new accumulator globes and probably a torsion bar adjustment. But read, read, read. :)
 
I keep reading that AHC is to be avoided. I never use it. I didn't know the shocks were specific to the AHC. Thank you for letting me know. I have an 80 that is much more simple.

I searched for a non AHC 100 but the truck I ended up buying had it. Like most people I had planned to ditch it once it needed some investment to keep going but now that I've learned how it works and the advantages it has I'll keep it for as long as I can get parts and fluid for it. It's an awesome system once you get to know it (and start using it as intended!)
 
I searched for a non AHC 100 but the truck I ended up buying had it. Like most people I had planned to ditch it once it needed some investment to keep going but now that I've learned how it works and the advantages it has I'll keep it for as long as I can get parts and fluid for it. It's an awesome system once you get to know it (and start using it as intended!)
This is the right answer if you're keeping it pretty stock.
 
I keep reading that AHC is to be avoided. I never use it. I didn't know the shocks were specific to the AHC. Thank you for letting me know. I have an 80 that is much more simple.
No leak. Truck just feels like the shocks are too soft and the truck is tipsy. The PO had the AHC flushed and serviced at around 120k. I guess I just don't know enough about this truck.
As with most things in life, it's not that scary once you comprehend it. Simple it is not, but it is reliable and beneficial in many ways. Plenty of enthusiasts (myself included) enjoy AHC for daily driving a stock vehicle and wheeling an armored up "rig". By no means should you "avoid it" as a blanket statement.
I searched for a non AHC 100 but the truck I ended up buying had it. Like most people I had planned to ditch it once it needed some investment to keep going but now that I've learned how it works and the advantages it has I'll keep it for as long as I can get parts and fluid for it. It's an awesome system once you get to know it (and start using it as intended!)
I did not expect to see you say such positive things about AHC, but I'm glad you came around. :)
 
I keep reading that AHC is to be avoided. I never use it.
Amen to all the previous responses.

"I never use it"???? Well, actually you do use it. Whenever the vehicle is in operation. Unless the system is switched "OFF" or faulty. In either case, a flashing green "AHC OFF" light would show on the instrument panel.

When folks talk or write about "AHC", it actually is shorthand for two integrated systems:

1. Active Height Control (AHC) -- which causes the vehicle to self-level automatically whenever the vehicle is operating, in real time, all the time, regardless of load, without driver intervention -- this part of the system is in use full-time provided that the system is switched "ON", not overloaded and not faulty.

In addition, the driver has the option of selecting three heights at the centre console switch -- "LO", "N", "HI" -- subject to specified limits, mainly speed. Maybe it is this optionality which is never used??

2. Toyota Electronic Modulated Suspension (TEMS) -- which causes the vehicle to adapt the damping settings automatically in up to 16 steps in response to physical road conditions, speed, use of brakes, cornering and a few other things, also in real time, changing in milliseconds, all the time, regardless of load, without driver intervention -- this part of the system is in use full-time provided that the system is switched "ON", not overloaded and not faulty.

In addition, the driver can select four damping 'maps' at the centre console switch -- from "Comfort" through to "Sport". Maybe this optionality also is never used??

By the way, the 'shock absorbers' on an "AHC-equipped" LC100 or LX470 vehicle are merely hydraulic struts used by the system to respond to the damping and spring requirements when the vehicle is moving, and to self-level the vehicle automatically, and when the driver to selects an optional height. Damping is done within small devices called "Damping Force Control Actuators" -- one for each wheel, located on the outside of the chassis rails, and to which are attached the round steel-cased nitrogen-filled gas springs (usually called 'globes' on this Forum). The so-called 'shock absorbers' on an AHC vehicle probably have an almost indefinite life unless they are subjected to long periods (months or years) of unadjusted excessive AHC system pressure leading to seal failure and leakage, or, unless extreme rust is evident.

Obviously, everybody has the right to accept or reject or 'avoid' the AHC/TEMS systems and decide what is fit-for-purpose in their circumstances. The systems often are rejected by people who have
  1. severe system damage (especially pipework) due to extensive underbody rust, or,
  2. no interest in the system, or,
  3. no interest in performing the simple maintenance and parts replacement requirements of the system, nor carrying out the resuscitation needed after acquiring a long-neglected system ('simple' means simple compared to brakes, transmission, fuel system, electrical system, engine systems, etc, etc, etc, on the vehicle), or,
  4. listened to or read adverse anecdotal stories on this or other forums without doing their own research, or,
  5. concerns about reliability in very arduous conditions.
Item #5 often is overstated except in the most extreme off-road, over-rock circumstances. However, it is always true that 'hard yards' will expose maintenance shortcomings.

It is not hard to find real success stories, involving vehicles which are anything but stock, with very heavy builds, in very tough conditions, and which have well-maintained AHC/TEMS systems in USA, Europe, South America, Australia and elsewhere.

Following @suprarx7nut, @ClassyJalopy, @Moridinbg and many others and seeing where they go with their vehicles provides good insights. The common thread is a deep understanding of the suspension and other systems on the vehicle given the build and load carried, attentive maintenance and very careful pre-trip preparation.

If interested in how the AHC/TEMS systems work, the attached General Description is a good introduction.

If interested in maintaining or repairing or adjusting the AHC/TEMS systems, this thread is a good knowledge base:
 

Attachments

  • AHC-TEMS for LX470 and LC100 - General Description and Diagrams.pdf
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Last edited:
Like I said… do some research on here for how to maintain AHC. Lots of great threads.

The amount of variability between full soft and full sport on my truck is night and day. Full soft is like a 60s Cadillac and full sport is like tuned coils on a German car. Obviously this is still a Lexus, but you should be able to notice a change in how it rides when you adjust settings.

My guess is you need new accumulator globes and probably a torsion bar adjustment. But read, read, read. :)
I drive the truck on the sport setting almost exclusively and it handles like a canoe- very tipsy.

Amen to all the previous responses.

"I never use it"???? Well, actually you do use it. Whenever the vehicle is in operation. Unless the system is switched "OFF" or faulty. In either case, a flashing green "AHC OFF" light would show on the instrument panel.

When folks talk or write about "AHC", it actually is shorthand for two integrated systems:

1. Active Height Control (AHC) -- which causes the vehicle to self-level automatically whenever the vehicle is operating, in real time, all the time, regardless of load, without driver intervention -- this part of the system is in use full-time provided that the system is switched "ON", not overloaded and not faulty.

In addition, the driver has the option of selecting three heights at the centre console switch -- "LO", "N", "HI" -- subject to specified limits, mainly speed. Maybe it is this optionality which is never used??

2. Toyota Electronic Modulated Suspension (TEMS) -- which causes the vehicle to adapt the damping settings automatically in up to 16 steps in response to physical road conditions, speed, use of brakes, cornering and a few other things, also in real time, changing in milliseconds, all the time, regardless of load, without driver intervention -- this part of the system is in use full-time provided that the system is switched "ON", not overloaded and not faulty.

In addition, the driver can select four damping 'maps' at the centre console switch -- from "Comfort" through to "Sport". Maybe this optionality also is never used??

By the way, the 'shock absorbers' on an "AHC-equipped" LC100 or LX470 vehicle are merely hydraulic struts used by the system to respond to the damping and spring requirements when the vehicle is moving, and to self-level the vehicle automatically, and when the driver to selects an optional height. Damping is done within small devices called "Damping Force Control Actuators" -- one for each wheel, located on the outside of the chassis rails, and to which are attached the round steel-cased nitrogen-filled gas springs (usually called 'globes' on this Forum). The so-called 'shock absorbers' on an AHC vehicle probably have an almost indefinite life unless they are subjected to long periods (months or years) of unadjusted excessive AHC system pressure leading to seal failure and leakage, or, unless extreme rust is evident.

Obviously, everybody has the right to accept or reject or 'avoid' the AHC/TEMS systems and decide what is fit-for-purpose in their circumstances. The systems often are rejected by people who have
  1. severe system damage (especially pipework) due to extensive underbody rust, or,
  2. no interest in the system, or,
  3. no interest in performing the simple maintenance and parts replacement requirements of the system, nor carrying out the resuscitation needed after acquiring a long-neglected system ('simple' means simple compared to brakes, transmission, fuel system, electrical system, engine systems, etc, etc, etc, on the vehicle), or,
  4. listened to or read adverse anecdotal stories on this or other forums without doing their own research, or,
  5. concerns about reliability in very arduous conditions.
Item #5 often is overstated except in the most extreme off-road, over-rock circumstances. However, it is always true that 'hard yards' will expose maintenance shortcomings.

It is not hard to find real success stories, involving vehicles which are anything but stock, with very heavy builds, in very tough conditions, and which have well-maintained AHC/TEMS systems in USA, Europe, South America, Australia and elsewhere.

Following @suprarx7nut, @ClassyJalopy, @Moridinbg and many others and seeing where they go with their vehicles provides good insights. The common thread is a deep understanding of the suspension and other systems on the vehicle given the build and load carried, attentive maintenance and very careful pre-trip preparation.

If interested in how the AHC/TEMS systems work, the attached General Description is a good introduction.

If interested in maintaining or repairing or adjusting the AHC/TEMS systems, this thread is a good knowledge base:
thanks for sending this information.-- very helpful
 
I drive the truck on the sport setting almost exclusively and it handles like a canoe- very tipsy.


thanks for sending this information.-- very helpful
With AHC functioning as it should, it will reduce tip and dive to a significant degree. It sounds like your system may have some old fluid (old fluid can get moisture and air in the mixture and allow it to become a little compressible which negates the intended effect of the fluid) and/or you've got old/dead globes. The fluid and the globes are wear items and easy to swap out. The globes are essentially the "shocks" of the system. Globes are cheap right now with the yen being valued much lower than the dollar. The popular exporter for AHC stuff ships a full set for something like $600. Local US dealers charge something like $4500 for a set - full-on highway robbery. Much of the AHC-hate you see is driven by folks that were facing dealership-pricing on service and parts which are essentially meaningless numbers. The markup on AHC components (and of course most components in general) is astronomical.
 
^ this. Replacing the globes was one of the easier projects I’ve done with noticeable difference in handling. Check out the “impex is legit” thread on how to order the globes and what wrench to order to remove the globes.
 
You may want to measure fender heights from the hub and compare to the stock settings. If it’s tipsy, the system might just not be balanced correctly, regardless of new fluid. I’ve done all of my AHC maintenance myself and the system is beautiful at 250k
 

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