No you want it to lower down to the bump stops, where it will sit until you restart and recharge the system.
Changing out the AHC suspension fluid? (2 Viewers)
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Thankyou. Attempting it for first time so bit hesitate. When car lowers you basically know it's lowered to the bump stops right is it suppose to lower always as have read a view posts were some times it doesn't. Paddo do you remove the filter bit in the AHC tank to take out the old fluid with a syringe style or kitchen dropper.Thankyou
Yes, you'll need to take the screen in the reservoir filler out so you can get your syphon hose or whatever in then replace it prior to refilling with fresh fluid. When you crack the bleeders for the front and rear circuits fluid will be expelled because it's under pressure, gravity will lower the vehicle and when fluid stops flowing it has lowered as much as it will which should coincide with it sitting on the bump stops or very close to them.
My 07 LX AHC hasn't been serviced in a while. Fluid looks great. Could I just drop it to the low setting and suck all the fluid out of the reservoir and then refill with fresh fluid? Figured that while all new fluid is ideal, swapping some of it with fresh fluid would be a good start.
If you're gonna spend the money (~$40) on the 2.5L fluid, why not replace it all
Only takes another ~10 mins to empty the globes (which is where most of the dirty fluid is).
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uHu
Bridgeburner
Not much point in changing the fluid in the reservoir. The fluid doesn't circulate in the system, and it's the bottom which is the business end. At the top, the fluid is always (nearly) good as new, even when the volume between the shock (ram) and accumulator is foamy, black or watery.
Changed mine today fluid was very dirty.I used PADDOS system very helpful.I may have to get another can of fluid as mine is just sitting above minimum now in N.Is it suppose to sit between Minimum and Max.
Between min and max at N height with engine running. If it was really old and dirty then consider doing another fluid change in a week or three after you've put some miles and up/down cycles on the system to further reduce and dilute the old residual fluid. You can then set the level in the reservoir higher, there's no issue with going a bit over the max level.
My experience so far....
I used PADDO's 1-can method for my first AHC fluid replacement on my new-to-me '98 LX470 with 160k miles on it... It was very simple and easy when following his procedure even though my confidence level was low going into it. Very good instructions!
Also, for others reference.. Not sure if my fluid had been replaced before, but in the reservoir in the engine compartment, the fluid was a transparent black color. Not like motor oil, but like watered down coffee. From the accumulator it was the same. From the left globes it was a similar color but with some micro bubbles coming down the hose. And from the right globes it looked like a mix of that dark stuff along with the new red fluid with no bubbles.
All in all, I added 2.5 liters and took out 2.5 liters.
Result: My pressures dropped slightly since the change and ride is improved. (from 8.2 avg up front down to 7.8 and from 7.1 in back down to 6.6) Also - Before the change, my left side of my truck seemed to sag a bit and looked a little lower than the right side. Since changing fluid,they are both even and level now EDIT: The left rear seems to be sagging a bit again. Maybe by about an inch... Before change I was getting 7 notches L to H, now I'm getting just over 8.
Next up: My pressures are still high in front and slightly so in back, so next up will be adjusting torsion bars up front, and then seeing where my rear sits. I expect I'll have to replace those rear springs to get pressures down after the front adjustment.
In my truck, I'm running all stock, but I've removed my trailer hitch and 3rd row seats, and also removed running boards. I hope this shared experience is helpful to someone else!
I used PADDO's 1-can method for my first AHC fluid replacement on my new-to-me '98 LX470 with 160k miles on it... It was very simple and easy when following his procedure even though my confidence level was low going into it. Very good instructions!
Also, for others reference.. Not sure if my fluid had been replaced before, but in the reservoir in the engine compartment, the fluid was a transparent black color. Not like motor oil, but like watered down coffee. From the accumulator it was the same. From the left globes it was a similar color but with some micro bubbles coming down the hose. And from the right globes it looked like a mix of that dark stuff along with the new red fluid with no bubbles.
All in all, I added 2.5 liters and took out 2.5 liters.
Result: My pressures dropped slightly since the change and ride is improved. (from 8.2 avg up front down to 7.8 and from 7.1 in back down to 6.6) Also - Before the change, my left side of my truck seemed to sag a bit and looked a little lower than the right side. Since changing fluid,
Next up: My pressures are still high in front and slightly so in back, so next up will be adjusting torsion bars up front, and then seeing where my rear sits. I expect I'll have to replace those rear springs to get pressures down after the front adjustment.
In my truck, I'm running all stock, but I've removed my trailer hitch and 3rd row seats, and also removed running boards. I hope this shared experience is helpful to someone else!
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Thanks from Hamilton New Zealand to all the contributors to the many posts on the AHC. I am finally today back to the armchair ride I started with when I purchased back in 2001, my 100 series 4.2litre Diesel turbo intercooledVX Limited with all the fruit including wall to wall leather and of course the AHC system . After replacing my steering rack in January this year after 420,000 kms my ride quality turned into concrete custard pie. My local Toyota folk were perturbingly scratching their collective heads and asses with no immediate solution. After finding this website with help from Aunty Google and after reading/rereading/printing/quoting/showing my tech at Toyota key posts and pictures we sorted out the issue. Some Monkey at the contracted wheel alignment place had used the wrong model to do the wheel alignment (200 series non AHC) and managed to torque up the torsion bars in the front way beyond what was required and the front ride was something out of the Flintstones era. I showed my Toyota tech a photo of the required testing device which he managed to find and we used it to check the pressures of the AHC system and consequently adjust the torsion bars to find the sweetspot of 6.9 MPa. We checked the rear pressure and found it was 7.5 which in my figuring was caused by a weak spring so another OEM spring has been ordered from Japan and should lower that pressure to a more acceptable level. Hopefully it will also alleviate the drop down into low height and stay there default that occurs if I load my wagon to the hilt as I have a tendency to do especially if the missus insists on taking the kitchen sink with us on a trip..
Again I am much appreciative of the collective wisdom and contributions gathered together on this website.
Tony Magner
Hamilton
New Zealand
Again I am much appreciative of the collective wisdom and contributions gathered together on this website.
Tony Magner
Hamilton
New Zealand
A big thanks from Australia. Did the AHC bleed today. The fluid that came out of the system on my 05 LeX470 was a terrible brown colour and foamy. The instructions in the PDF on this thread were brilliant.
Interestingly, the accumulator was still on the left hand side of the car (so the passenger side of an Aussie car, but driver's side for the US).
I found Toyota less than helpful in providing the replacement fluid - guy told me that they only had it in large drums in the service workshop. This was despite me being almost 100% certain I could see it in a can on the shelf behind him. Took my business to Lexus and they sold be a 2.5Litre can for $25 - was pretty happy with that.
I'm not sure if it has fixed the bouncy ride as yet, I'll drive it for a bit and maybe do another bleed in a months time. Given the old fluid was a bit foamy it seems there might be a bit of air in the system
What I do find however, is the car will not stay in L or H - as I being to drive it reverts back to N. In H it seems to trigger this above about 20km/h and from L almost immediately after I started to move again. I'm guessing this is not normal? If this some sort of sensor issue?
Interestingly, the accumulator was still on the left hand side of the car (so the passenger side of an Aussie car, but driver's side for the US).
I found Toyota less than helpful in providing the replacement fluid - guy told me that they only had it in large drums in the service workshop. This was despite me being almost 100% certain I could see it in a can on the shelf behind him. Took my business to Lexus and they sold be a 2.5Litre can for $25 - was pretty happy with that.
I'm not sure if it has fixed the bouncy ride as yet, I'll drive it for a bit and maybe do another bleed in a months time. Given the old fluid was a bit foamy it seems there might be a bit of air in the system
What I do find however, is the car will not stay in L or H - as I being to drive it reverts back to N. In H it seems to trigger this above about 20km/h and from L almost immediately after I started to move again. I'm guessing this is not normal? If this some sort of sensor issue?
Not s
Not sure on this Paddo best to ask or if someone else can give input.My does this sometimes to in L.
Not sure on this Paddo best to ask or if someone else can give input.My does this sometimes to in L.
Flipped Bezel
Here for a good time...not a long time!
I'm pretty sure this is a normal function of the AHC system. Once you get over a certain speed the system automatically adjusts back to the neutral position.
You'll probably want to read up on adjusting your neutral pressures and checking your 4x damper accumulators are still serviceable with the L to H reservoir graduation check. Here's how the speed sensing works - basically it wants to go back to N.
Thanks so much for your replies PADDO/Flipped Bezel. That is good to know. Got my measuring tape out and its almost perfectly the same across the fronts but they are only about 19", so looks like I need to wind up the TB's. The rears are at about 21.5" (so certainly a bit high). I've read this entire thread and a few others and I wasn't sure on whether people do the TB adjustment with the car on jacks or not. Presumably easier to do while the wheels are off the ground but means a bit of up and down to check measurements etc.
Before I do all of that I do want to check the pressures, but I'm unsure as to what units will actually work on an Aussie 2005 model. Most scanner websites seems to say only 2006 on-wards. I checked with an Ebay site about the TOYOTA Techstream TIS V10 MINI VCI USB Interface OBD2 Car Diagnostic Cable unit ($50) and he says it will work provided I have Windows XP. I did notice that a few people on here did mention that so I know there are a number of ways around this issue. However, he recommended the AUTEL AutoLink AL619 OBD2 ABS AIRBAG Diagnostic Car Scanner which is +4 times the price ($240). Have any Aussies on here had any success with any units and have any recommendations?
Before I do all of that I do want to check the pressures, but I'm unsure as to what units will actually work on an Aussie 2005 model. Most scanner websites seems to say only 2006 on-wards. I checked with an Ebay site about the TOYOTA Techstream TIS V10 MINI VCI USB Interface OBD2 Car Diagnostic Cable unit ($50) and he says it will work provided I have Windows XP. I did notice that a few people on here did mention that so I know there are a number of ways around this issue. However, he recommended the AUTEL AutoLink AL619 OBD2 ABS AIRBAG Diagnostic Car Scanner which is +4 times the price ($240). Have any Aussies on here had any success with any units and have any recommendations?
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Hi casdawg.
I have the 2002 LX470 and use a mini VCI from ebay. My car has M-ODB under the dashboard, close to the gas pedal.
I have the 2002 LX470 and use a mini VCI from ebay. My car has M-ODB under the dashboard, close to the gas pedal.
