Im looking to upgrade my tires to some 285/70/r17s, but I don’t want a lift kit. Ahc has a high position but it goes back down to neutral. Is there a way I can lock my ahc system at high?
Lexus AHC Lock
- Thread starter ytrakas
- Start date
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Welcome to the forums.
Gotta read the stickies at the top. Lots of information there.
forum.ih8mud.com
That will tell you what you need.
Gotta read the stickies at the top. Lots of information there.
FAQ - 100-series FAQ
forum.ih8mud.com
That will tell you what you need.
You can lock it in high only up to 50mph. To do it you need to be in neutral height, press the AHC up button, wait one second, press the AHC OFF button , immediately turn off the ignition, when you restart the truck it will stay in high until you reach 50mph then will automatically go to neutral.
If that's a 33 you probably don't need a lift anyway.
The pic below shows the OEM details of the AHC height/speed arrangements. Some have used a bypass of some kind to maintain "HI" height without reverting to "N" at any (?) speed. Suggest bear in mind that AHC pressures are much higher at "HI" than at "N" -- you can measure this on your vehicle by doing the Techstream AHC pressure readings in the standard way, except raise from "LO" directly to "HI" when doing the test.
Visualise the 'globes' at "HI" on the road in this condition. At these high hydraulic AHC pressures, the nitrogen pressure behind the diaphragms in the 'globes' will be insufficient for the 'globes' to respond in the same way as they would at "N". The inevitable effect will be a stiffer ride with much less damping, along with prolonged high pressures challenging the seals at 'Shock Absorbers' and elsewhere -- unless of course you counteract these effects with stronger rear springs and adjusted or stronger torsion bars -- much like doing a 'lift' which would appear to defeat your purpose?
Source: https://lc100e.github.io/manual/ then tabs New Car Features (first item in the list) >CHASSIS > Suspension > Active Height Control Suspension & Skyhook TEMS.
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Flipped Bezel
Here for a good time...not a long time!
Use the search function in the upper right corner of this page for "AHC Lift" on this forum. There are many useful threads that explain how you can gain a free lift for simply adjusting the height sensors. This should be done only after understanding the AHC suspension functions and acquiring the diagnostic system to evaluate and make adjustments your system.
I recommend researching the topic and mod thoroughly before performing the lift. There are consequences and you should attempt to keep your neutral pressures in spec if you plan on keeping your AHC functioning long term.
I recommend researching the topic and mod thoroughly before performing the lift. There are consequences and you should attempt to keep your neutral pressures in spec if you plan on keeping your AHC functioning long term.
You do NOT need any lift, at all, for those tires.
Do not override AHC heights until you understand the system very well.
Forget the lift. Buy the tires. Welcome.
Do not override AHC heights until you understand the system very well.
Forget the lift. Buy the tires. Welcome.
The last time that I measured AHC (front) in "H" it was ~21.5" from the center of the hub to the fender, and "full droop" was ~22.75". Running in "H" at road speeds doesn't leave enough "droop" (~1.25"), which causes it to ride like s***.
Assuming that you don't go crazy with aftermarket wheel offset, 285/70R17 should fit just fine, no matter the AHC setting (same for 285/75R16, 285/65R18, and 275/70R18).
Assuming that you don't go crazy with aftermarket wheel offset, 285/70R17 should fit just fine, no matter the AHC setting (same for 285/75R16, 285/65R18, and 275/70R18).
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ramangain
Clarksonian disciple
Be the rebel. Raise AHC to H and disconnect the AHC pump motor and ECU. Let us know how it works out for you.
