Disadvantages to lifting the LX570 via height control sensors? (Sensor Lift) (1 Viewer)

[chriscosta416]

Hi all,


I have been attempting to read up on all the AHC posts for the 200 series and I am wondering what are the downsides to lifting the LX570 via the height control sensors?

From my understanding you are

- putting more stress on the AHC system
- Reducing load carrying capacity
- Potential for a harsher ride?

I maxed out the sensors for fun and then returned them to stock height.


If anyone could chime in or point me in the right direction I would greatly appreciate it!

 

[barcelona4x4]

i moved my fronts up halfway to level it with the rear. It rides no different than factory. Roughly an inch of lift and is an option if you're concerned about any of the points above.

 

[lx200inAR]

You pretty much covered it. Less droop is also a “feature” of sensor lift. I don’t know if I’d word it all the same. Sensor lift causes higher system pressure, whether that causes a meaningful higher stress level or not hasn’t really been proven I don’t think. The higher system pressure means your springs are doing less, so that could lead to an imbalance and harsher ride. I also did a max lift and ended up bringing it back down. I think the state of your globes can augment how bad the extra lift behaves. Personally if I was going to lift, I’d do something with spacers to get the spring preload more balanced.

 

[TeCKis300]

Hi all,


I have been attempting to read up on all the AHC posts for the 200 series and I am wondering what are the downsides to lifting the LX570 via the height control sensors?

From my understanding you are

- putting more stress on the AHC system
- Reducing load carrying capacity
- Potential for a harsher ride?

I maxed out the sensors for fun and then returned them to stock height.


If anyone could chime in or point me in the right direction I would greatly appreciate it!

View attachment 3050034

1) Putting more stress on the AHC system

The AHC system is balanced at factory ride height to have a portion of the vehicle weight carried by the physical coil springs and the remaining portion by the AHC hydraulic system. AHC normally has reserve capacity to bear more of the weight as it would in AHC high (because coils springs relax with height). That reserve capacity is also meant to carry up to the max payload of the car.

2) Reducing load carrying capacity

Challenge lies in that if you use up the reserve capacity for more sensor lift, it may not be able to lift to high, and/or it can't take max payload to the higher position. There's solutions to augment and you can pre-load the springs with spacer both at the front and rear. At the rear, there's also options to use airbags or uprated springs. See LX570 Augmenting for Load - https://forum.ih8mud.com/threads/lx570-augmenting-for-load.1008666/page-2#post-14260557

3) Potential for a harsher ride?

I believe this can happen on two fronts.
a) Worn globe accumulators in combination with putting more load on AHC. Worn globes in the sense that they have lost a portion of their ~400PSI charge, requiring more hydraulic volume to achieve the pressures. However, the AHC globes are bottoming out hence the reported harsher ride
b) Too much sensor lift and not leaving enough suspension droop travel. A good rule of thumb developed by the 100-series guys is to leave ~2.5" droop travel in high. Without that, the utility and articulation of high mode may not work well. With stock AHC, the front has 9" total travel, with normal ride height splitting 3.5" compression to 5.5" droop travel. Rear, 10", 4.125" compression, 5.875" droop. The stock setup keeps a big travel bias in droop, and why it feels good and slinky. In AHC high, still keeps a solid 3.5" in droop, front and rear. Challenge comes when sensor lifting aggressively. For example, a 1.5" sensor lift leaves only about 2" droop travel F and R in high. Sensor lift higher, and it's pegged out, stiff legged, with no articulation. So the sweet spot is to keep sensor lifts no more than about 1.5". Unless doing a long travel AHC mod

 

[chriscosta416]

@TeCKis300 appreciate your response! I maxed out the sensors however now I am having a hard time getting it back to a little over stock height, any tips?

I have parked on level ground, turned off AHC, turned off car, adjusted, turned car back on and its getting tedious. Any way stock measurements I can follow? Old witness marks are gone.

 

[chriscosta416]

nevermind, I figured it out! I placed a basket ball on my driveway and turns out, it has a very very slight slope that was skewing my perception.