@radman Thank you, but in the HOU, do I enter the values you mentioned or do I do my own based off my numbers?
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AHC Height Offset Utility How-To
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Jason Andrews
Modaholic
I know someone has asked this question before, but I can't remember the answer. Can you use Techstream to manipulate the speed at which the AHC lowers at highway speed? OEM setting is 65mph on the speedometer and with tires I have to hit 73mph before mine lowers. I wouldn't mind if it was set even lower ~55mph. Is this possible?
Nope
No ones achieved this yet. I've been pondering too as when towing, it really helps stability in higher speeds for it to lower and further tension my weight distribution bars.
It's not very likely to be able to change the threshold at which the system lowers programmatically, unless someone gets access to the developer tools.
What's more likely is to intercept and correct the speed signal on the CANBUS.
Please someone smart, do this for us! For all eight of us that want it
TN LX570
SILVER Star
Agreed. I’ve chased this in spurts when time allows. I believe there is another signal sent to the AHC ecu that sets the current height restrictions in addition to the VSS signal.
I spliced one of the hypertech speedo correction units in line directly at the AHC ecu on the CANBUS lines. As I believe that’s how those work when used in their intended form at the gauge cluster. They intercept the CANBUS lines and adjust the output into the gauge cluster and speedometer.
It had zero effect at the AHC ecu. I think there’s another signal sent for each height mode allowance that needs to be modified or replaced.
I have logs of can packets and using various softwares have been able to send back to the truck and manipulate different functions (temp control, door lock, etc) but it’s tedious to sort through and I haven’t devoted anymore time to it.
Please someone smart, do this for us! For all eight of us that want it
Here's our guy!
Thanks and I hope you might keep chasing this!
Davey, can we purchase more of your devoted time to it?
If you look at the AHC Datalist in Techstream, the AHC ecu actually tracks the speed at each wheel. I suspect the dashboard gets a single speed from one of the ECUs (Guessing the ABS/Skid Control) that probably uses the 4 signals to generate one speed (i would assume whatever the lowest speed is). This probably complicates using something like the inline speedometer calibration tool to work on the AHC ECU.
Jason Andrews
Modaholic
Davey, can we purchase more of your devoted time to it?
I didn't know this responsibility would land on @TN LX570- I already have a request in to verify the "how to" bolt in LX600 shocks and get it to jive with the rest of the system first
@radman
Forgive me, just got a 14 LX and don't want to screw it up, I ender my calculated 4.x value and a stock value of 4.0 on this popup, right?
running max sensor and Techstream lift. Anyone experiencing issues with vibrations or slightly bouncy ride running at 75-80mph? Tires are good and balanced (twice from 2 different shops to confirm). The feeling is like an out of balance tire. Was going to try backing down the Techstream lift a bit to see if that helps.
Or is this a AHC pressure issue... and would spring spacers help?
Or is this a AHC pressure issue... and would spring spacers help?
You are likely experiencing a combination of things especially with sensor lift plus HOU being maxed out:
- In my experience, sensor lift will exacerbate the symptoms of worn accumulators
- Sensor lift increases fluid pressure, making ride slightly firmer
- You are out of down travel
So recommendations would be drop down the height offset in Techstream and add the spri g spacers?
I'd suggest experimenting with some spring rubbers. It's not clear how heavy you are above stock, or what tire/rim you're running, but the investment in spring rubbers isn't much and they could alleviate the issue.
If you're on stock accumulators (10+ years old), then it's time to replace those as well.
If you're on stock accumulators (10+ years old), then it's time to replace those as well.
Stock 20" wheels running 34x11.50. 1" spacers. Only exterior mods are slee sliders. Changed my accumulators about 6 months ago hoping to alleviate this. I have bled the ach again to make sure there was no air trapped.
Spring spacers it is.
Just to be clear, spring rubbers may be different than spring spacers. Are you referring to a puck at the top of the spring/shock assembly, or a rubber insert into the spring to increase spring constant? I'm referring to the latter.
I guess I was referring to the spacers. I've seen the part number for the front spacer and then generic 30 mm spacers for the rear. I guess I'm not sure what the rubbers will do compared to the spacer.
