Solution to intermittent AHC lean?

[doru]

As others reported not long ago, the fact that there is no diff between sport and comfort it means you need to replace some of the AHC components. I think the guy reporting this changed the globs. Have a read here

AHC confort vs sport

forum.ih8mud.com

 

[Falmin]

I want to add some unprofessional tip that I have learned because dealers were refusing to work on a 15 year old car.

The lean can be solved by calibration on techstream. Turn off the hydraulic with the button and increase the height of the wheel that is not balance using techstream. After height is adjusted, calibrate with 0 before value and zero after value.

The next step is important because no one told me the exact procedure. Once the calibration is complete, do not reset memory, drive the car for 5 to 10 mins, park and do not turn off the engine, check the height after 5 mins. If the height is ok so go ahead with reset memory on techstream, otherwise repeat the process, increase the height of the particular wheel again and drive and check height. Without driving if you reset, next morning it'll go back down.

The importance of driving after calibration is so the other wheels adjust the new height pressures. If you reset memory right away, the side will go back down.

 

[2021 LC200]

Like the KDSS lean, AHC lean is a fallacy. Not that it doesn't lean, but it's not because of AHC or KDSS.

AHC as part of its operation, will equalize pressures left to right. So while it may appear to be able to level side to side, it will equalize at speed, or in transitions as you're finding.

Root cause, as for any slinky 4x4, is wear and settling of the coil springs. As cars age, a weaker side will show. With continual lean, more and more weight gets put on said coil, further causing the weaker coils to settle more than others.

Appropriate fix, like for KDSS, is to use coil shim packers. Readily available in 5/10/20/30mm sizes. We can't readily shim or trim the front spring. So a 5 or 10mm added to the rear spring in the low corner is the fix. Or new fresh springs, but nothing wrong with trim packers.

Adding to the points made by TeCKis300 which I agree with, lean in either KDSS or AHC can also be caused by parking on a non level drive way or parking spot. When this lean bothers you park in the other direction in the same spot or get techstream and reset on a level surface or just drive around and let it level again (unless as pointed out by TeCKis300 the springs or weight distribution of mods on the vehicle are the cause).