Basic question about AHC in a 1998 LX470 (1 Viewer)

[AggiePhil]

I've seen posts by guys with LX470s which reference setting the AHC to the highest setting all the time. Sounds awesome. However, in my 1998 LX470, I believe that the AHC will only allow the high (or "H") setting at very low speeds. Once the speed gets to a certain point, the suspension then goes down into "N" mode. Am I missing something? Do the newer LX470s let you lock the height into H mode permanently if you wish? Or am I mistaken about how mine can be set?

I know that there is also the Sport--Comfort knob (with settings in between), but my understanding of this setting was that it only had to do with the responsiveness of the suspension rather than the height of it.

 

[2000UZJ]

I've seen posts by guys with LX470s which reference setting the AHC to the highest setting all the time. Sounds awesome. However, in my 1998 LX470, I believe that the AHC will only allow the high (or "H") setting at very low speeds. Once the speed gets to a certain point, the suspension then goes down into "N" mode. Am I missing something? Do the newer LX470s let you lock the height into H mode permanently if you wish? Or am I mistaken about how mine can be set?

I know that there is also the Sport--Comfort knob (with settings in between), but my understanding of this setting was that it only had to do with the responsiveness of the suspension rather than the height of it.

Slee-Override thingy, or adjust the AHC sensors to ride at a higher height.


I'm not that knowledgeable on the AHC system. But those are the only tricks I am aware of

 

[1loudLX]

get the slee box. Least messing around, and when you want to hit the highway, you can easily drop it back down into perfect spec. I dont suggest doing it any other way.

 

[AggiePhil]

get the slee box. Least messing around, and when you want to hit the highway, you can easily drop it back down into perfect spec. I dont suggest doing it any other way.

Oh wow. That thing is badass! And only $50?! I can handle that! One question though... You say, "When you want to hit the highway, you can easily drop it back down into perfect spec." Does that mean that it'd cause problems to leave it in "H" while driving at highway speeds? I drive on the highway every day and would prefer to just leave it on "H" all the time if it wouldn't cause problems.

 

[1loudLX]

yes, you can leave it in high mode, but...some people like to drop it lower for cruising while being able to keep it raised in high mode at...higher speeds than factory settings allow offroad.

It's truly the best of both worlds having the little slee box. I see you have found the page on the website, but I'll link it here incase anyone else is wondering Slee - Electrical Switches

I never had the unit myself since I went the OME route, however I've been in trucks with it and it just makes it nice to be able to have total control over the AHC system instead of adjusting the sensors and getting dirty re-adjusting and fiddling and blah blah.

 

[hoser]

A couple things to keep in mind... you can only optimize alignment at one height. So, if you are planning on leaving it in HI on the freeway, I'd align it on the HI setting. Two, AHC on HI lifts the front less than the rear. So you may need to fine tune the height sensors.

 

[AggiePhil]

Two, AHC on HI lifts the front less than the rear. So you may need to fine tune the height sensors.

Alright, about that point... I put the truck into H mode and I see that the rear end sits higher, presumably loaded up for towing (as I think it also sits this way in N mode). Are you saying that I can somehow adjust the sensors to overcome this? If so, how difficult is it to do?

 

[hoser]

The rear end sits about an 1" higher in normal mode. But in HI mode, the rake is a bit more. I forget the exact measurement but you can easily measure it on your own if your are curious.

The height control sensors are very easily adjustable. One nut on the rear or two on the front.

 

[Jrob80]

I am still trying to get used to this AHC deal in my 00 LX470. I have been reading as much as possible but there are so many threads to wade through to get to what you are trying to find out exactly.

With the Slee box can you set it to ride in Low all the time as well? It sounds like there are just two settings High and OEM setting?

I would thinking going down the hwy there would be an advantage of setting your vehicle to its lowest setting, maybe I am wrong though? Is there a way to keep it at it's lowest setting everytime I mess with it, it goes right back to "N"?

 

[agaisin]

With the Slee box can you set it to ride in Low all the time as well? It sounds like there are just two settings High and OEM setting?

I would thinking going down the hwy there would be an advantage of setting your vehicle to its lowest setting, maybe I am wrong though? Is there a way to keep it at it's lowest setting everytime I mess with it, it goes right back to "N"?

Different manufacturers have different types of ride height control systems, intended to be used different ways.

A friend with an LR4 says it's capable of driving in L or H ride height at highway speeds.

That's not the case with LX470 - the Lexus system is designed to automatically go to N at ~19mph iirc. The suspension is not designed to be driven at highway speed (or really > 19mph) in H or L. In L you're on the bump stops, and in H I can only guess at the other issues (rollover risk, out of alignment, etc).

See Slee's install instructions for the override for this warning about driving in Low (http://www.sleeoffroad.com/installation/LX470_height_control.pdf):
"The vehicle should not be driven in LOW mode. LOW mode is intended as a passenger loading feature. In LOW mode the hydraulic shocks do not have any dampening and driving the vehicle in this mode can cause dangerous conditions."

Here's what they say about driving in High all the time:
"NOTE: If you plan to drive the vehicle in high mode all the time, you need to have an alignment
done at that height, otherwise you can have accelerated tire wear.
"

(my own commentary - Slee must not think it's dangerous or damaging to the vehicle suspension to drive in H all the time (at high speeds) etc, but the fact that Toyota/Lexus specifically designed the system to go to N > 19mph makes me think they had a reason?)

 

[smwmustang]

This is obviously an older thread and I see SLEE does not list this anymore. Anyone have any other ideas or a switch laying around.