Rear Air Suspension

[Ridger]

I'm at 37 1/4 high
35 7/8 normal
35 Low

Thanks William.... that is what I suspected, and mine is lowering down to 34-35 almost everyday, but the compressor still works fine and will pump it back up again.

What I suspected is that i have a small leak.... however, thinking about it more, it would have to be a slow leak in both air-bags because it lowers eveningly. Hmmm... so takes me back to thining it might indeed be a sensor problem (or something along those lines).

 

[Ridger]

Is there no disable button for the suspension? When I did tires we had to disable the lincoln airbags when they came in or they'd deflate all the way... if you're lucky they'd pump back up.

The suspension has an "off" button, but it re-activates everytime you shut off the T4R and restart it.

I'm going to do some more research into if the air-bags can be set to the "level/Normal" ride setting and then disabled (hopefully fairly easily) so that if it is teh "salt" issue, I can disable in teh winter, then enable it again for the summer camping season.

Wish I had of known about this issue before I bought because I would not have gotten the rear-air. Its becoming a pain in the rear.... lierally - you have no idea how rough and bouncy the suspension is when it goes down all the way... I think it is sitting right on the frame.

 

[Ridger]

I found these two threads on this issue....

Auto leveling problem - Toyota 120 Platforms Forum

Stock Rear Ai\rbag Problem - Toyota 120 Platforms Forum

I'm going to try to set the air-bags to teh "normal" position and then pull the "fuse" to see if that will deactivate the air-bags but keep them inflated at that height (without deflating).

Hopefully that will work.... x-fingers.

 

[chaz]

if u got the $ u can replace em with coils. Stock Rear Ai\rbag Problem - Page 2 - Toyota 120 Platforms Forum http://www.toyota120.com/forum/showthread.php?t=2994&highlight=rear+air+suspenion&page=3

 

[ARK_SWAMP_RIDER]

The issue is that salt has corroded the sensors, the problem will not go away once they quit using salt, damage is done. One thing I think may work is that you can easily adjust the sensors to add more air at each setting. For example, I adjusted mine so that the normal position is about 1.5"-2" higher than before. I think if you did this, even if it sunk to the "low" position, it'd be equivalent to the previous "high" position.
Setting rear Air height on 4R/GX and Prado - Toyota 120 Platforms Forum

 

[Ridger]

if u got the $ u can replace em with coils. Stock Rear Ai\rbag Problem - Page 2 - Toyota 120 Platforms Forum Stock Rear Ai\rbag Problem - Page 3 - Toyota 120 Platforms Forum

That is where I might be headed. I'd prefer to keep the air-suspension for towing purposes which is a big reason for me getting the Limited over the Sport.

But thankfully at this point, nothing is "broke" so i still am ambel to adjust teh rear air. If that changes, I'll be forced to do a swap-out quicker. But I'm going to attempt a couple "fixes" to see how that goes (pulling fuse after setting hight to "neutral" ride height - and maybe cleaning sensors).

If I can ride this out (no pun intended) until summer, and then it goes back to normal I'll leave it be until next fall/winter - but it will drive me nuts having this issue throughout another full winter so I'll be forced to swap it out at some point in the future..... but it may be sooner then I think.

 

[Ridger]

The issue is that salt has corroded the sensors, the problem will not go away once they quit using salt, damage is done. One thing I think may work is that you can easily adjust the sensors to add more air at each setting. For example, I adjusted mine so that the normal position is about 1.5"-2" higher than before. I think if you did this, even if it sunk to the "low" position, it'd be equivalent to the previous "high" position.
Setting rear Air height on 4R/GX and Prado - Toyota 120 Platforms Forum

Hey, that may be another "fix", thanks Ark.

Do you think it is really permanent "damage", since the compressor and settings all still work okay? I've never had it "lock up" like other seems to have experienced. Mine just drops down, then I can get it to go back to the "neutral" settings again - sometimes it drops more then once a day, sometimes it stays for 2 days before dropping again?

I'm hoping that it may continue to work like this until spring/summer, then maybe once the salt is gone it will go back to normal (might have to clean the sensors first). Maybe just wishfull thinking?

 

[ARK_SWAMP_RIDER]

I hope I'm wrong, but I doubt that it'll get any better if left alone. I do remember someone on 120 taking some of it apart and repairing it. I'll have to see if I can find that post. I've seen several have it bottom out and wouldn't stay up, yours is different in the fact that it'll go back up just as you said.

 

[Husker Z]

I get that too when i stop, but i love how it tows. when people get into the car and the back raises i realy like it. it levels out the car.

as for towing, it is awsome. it is the first air suspension that ive had, but still, it levels out the runner.

I get this as well. Is it an issue I should have the dealer look at (I'm under warranty)?

Also, how do you know if you have the airbags? I have a 08 Limited 4WD, should I have it?

Thanks.

 

[ARK_SWAMP_RIDER]

There's a display by your tachometer and buttons to adjust settings on the center console.

 

[Ridger]

I hope I'm wrong, but I doubt that it'll get any better if left alone. I do remember someone on 120 taking some of it apart and repairing it. I'll have to see if I can find that post. I've seen several have it bottom out and wouldn't stay up, yours is different in the fact that it'll go back up just as you said.

Like I said.... I'm just holding out hope it starts working properly again (or should i say wishful thinking).

The top link of the two links I posted above shows pictures of the poster (landtank) that pulled his sensors apart and its shows the corrosion. There was talk about possibly being able to clean the springs & contacts in the sensor with contact cleaner. I'm going to try to give that a shot and cross- my fingers it works. You can see in the pcis he posted that the sensor has a rubber O-ring, but it obviously is not enough - if i take mine apart and clean it, I'll try some additional sealant to try to ensure a good seal for prevention.

Probably all for not unfortunately.

Anyone wanna buy a 2006 Limited V8? :wink2:

 

[Bossman]

Just took my 03 T4R for an oil/filter service at 135,000 km and the height control malfunctioned while up on the hoist. It jacked the back end up like a drag car.

They had to manually return the height to normal and then disable the height control.

The cost of repair to either the sensors or actuators and who knows what else is way too expensive (no longer under warranty), so I'll keep it deactivated.

Corrosion is likely a contributing factor to this malfunction.

Never used this technology anyways, so no real loss.

Update! With the sensors already gone, the compressor has now started showing early signs of failure.

My mechanic has now bypassed the RAS system completely. He has installed hoses, fittings and a valve that will allow me to inflate/deflate the rear air suspension manually (same type of valve that is on my tires).