You have a huge difference, very similar to where I was. I assume you did this in a flat as possible surface right? But I don't understand why are you installing new ones? this sensors rarely go bad, and what i see is that in your case they are just reporting a mechanical misalignment. They can go out of calibration because of dust and debris making them get stuck, happened to my old GS and now to the GX. When i started to troubleshoot thi issue my RH one was full of dirt, I remember I sprayed WD-40 to clean it and it was like a river of black crap coming out of those ball joints, after I then sprayed white lithium it was great, anyway, I see yours are measuring just fine you just need to calibrate them. Start calibrating the rear left one, the one right below the gas tank. Not that hard to accomplish, just need a 10mm wrench and patience, i did it myself, the hardest part was to have my laptop close to me while i was adjusting, lucky me I have a long OBD2 cable.

Oh and remember level them when you have a completely full gas tank and try not to have heavy objects in the truck, empty the trunk and just get close to curb weight as possible.

Also remember that the GX460 naturally have a lean that can be corrected replacing the LH front shock spring so dont expect both sides to be the same height, if you can get 0.0 and -0.2 max -0.3 you willl be very happy.

I hope you can fix it soon, I am 98% sure your rear harsh ride is because of this difference in the back, in normal position your right air back is rock hard trying to match your left one which will result in what you are expericing.

 

Thanks again, this is such a huge help. I read it on my driveway, which isn't level front to back, but is level right to left. I have rhino ramps - I might back up on to those to level off the stance and then start adjusting, if that sounds like it would work.

I have looked at them before and tried cleaning them with WD40 and lithium grease, but they didn't look all that dirty to me. I'll try that again before I change the adjustment. Which 10mm nut do you start with 1, 2, or 3?

Also, at normal values below, you mentioned rear left one (gas tank side) - so that should be 0.0, correct? And then at normal the Rear RH side should also be adjusted to 0.0 for normal, also?
Initial Sensor Values (Normal):

• Rear RH Sensor: -0.6"
• Rear LH Sensor: 0.8"
• Total Variance: 1.4"

Also - somewhat unrelated - but this means my air bags are likely OK at then? I dont hear a constant hiss/compressor running, only when I adjust the height up/down. But otherwise I don't hear anything...

 

Avoid the Rhino Ramps! You need the truck on a flat surface to get accurate live data.I was able to crawl under without a problem, and im not small height and 240 pounds, if not you might need a shop with a bay or simply put the truck in HI position adjust to eye, back to normal check TD values then go back down and repeat, longer but might work, but once again, I think you can do it in the normal position tho.

To adjust, loosen the 10mm nut on the bottom adjustment rod (Nut 3). This allows the arm to slide. Slide it in small increments, then check Techstream.

Aim for 0.0 on both, to mark the original position with a Sharpie before you move anything so you have a home base, but keep in mind that since the fuel tank is on the Left Hand (LH) side, you might end up preferring a value of -0.2 or -0.3 on that side to perfectly level the Lexus Lean. If you are able to crawl down there and start adjusting remember you need to have the truck empty and idling, if you have someone reading the live data of the sensors even better or if you dont care for your laptop bring it under the car as i did, lol.. that you can keep adjusting on the fly, try to find a flat as possible surface!

Regarding your bags: If they aren't sagging overnight and your compressor isn't running constantly, they are likely in great shape, I did check mine as well with soapy water just in case and they are superb, specially since I live in trhe tropics, no snow or salt that can accelerate bags failure.

Your rough ride is almost certainly because the computer is confused by that 1.4" difference between the sensors, making one bag way too stiff!

 

Ok good deal. I was going to use the rhino ramps on the rear to prop up the rear of the vehicle to match the front, so that the vehicle would be level on an unlevel surface. Another quick question - do these height sensors move when I the AVS system is engaged? Meaning if I have someone hit the height (HI) button while I am under neath, would I see anything move on the height sensors?

The only thing I can think of is that when the shop replaced my rear shocks that the tech fiddled with this sensor or something - maybe hit it inadvertantly or something, which caused the mis-alignment/zeroing out.

I do agree - it sounds like my issue is directly related to the height reading of these sensors, causing the airbags to stay inflated and providing a rough ride..I'll follow up when I'm done this weekend.

 

I really recommend against the ramps. Even if the body looks level, the weight of the engine shifting on an incline will preload the suspension, and your calibration will be off the moment you drive onto a flat road. It’s worth the 5 minute drive to a level parking lot to do this.

Regarding the movement: Yes, the sensors move! As the air bags lift the truck, the linkage rotates the sensor arm. Be careful u don't have anyone touch those buttons while you are under there unless you have jack stands supporting the frame. You don't want to get pinched if the system reacts suddenly.

It’s very possible the shop bumped a sensor while doing your shocks. Those brackets are thin, and even a slight bend will throw your 'Normal' height off. Adjusting Nut 3 to get those values back to 0.0 (or -0.2 on the LH side) is the exact reset your AVS system needs to stop hitting those bump stops

 

Alright! I was able to dial in the adjustments so they are both within 0.1 of each other. I didn’t use the rhino ramps, just did it on my driveway. Went back and forth until I got them dialed in.

ride is so much better now, night and day difference. I am going to do the calibration on level ground too, but it’s been a huge success.
thanks so much for your help!

 

I am very happy I could help! I also have to make the calibration on a leveled ground I will try to do it next wknd

 

the service docs should have where to measure for the height at the rear when adjusting.
you can also use those height sensors to slightly raise or lower the rear which will also impact ride harshness, but this really isnt needed for most people. tire pressure can have almost as much impact.

 

I have techstream v 18.00.008 11486 and I don’t see the calibration for the auto ride height sensors. can anyone point me to it?

id like to calibrate my rear airbag system now that i have them dialed in.

thanks!

 

Actually, there isn't a one-click auto-calibration button in Techstream, at least I didnt found it. You have to perform a manual adjustment while using the software as your reference point.

Here is the standard process to dial them in

Park on a leveled surface with a full tank of fuel and an empty vehicle and check all your tires pressure to be in the correct pressure, 32 kpi.

Connect and go to Chassis > Air Suspension (or AHC) > Data List.
Look for the Height Sensor values (Left and Right).
You’ll need to physically adjust the sensors linkages/brackets located on the frame near the rear wheels, one is right behind the gas tank and the other on the opposite side. Loosen the adjustment nut and slide the linkage while watching the live data in Techstream.
Adjust them until the readings match your desired height or the factory '0mm' offset.