Was this the first service?
Props to PADDO's AHC fluid replacement method!
- Thread starter Clunky
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Was this the first service?
I believe this was the first service. I'm the second owner and I have all the service records from the first owner who maintained it exclusively at Lexus of Albuquerque. There was no record of any work done to the AHC system.
My rig rides great, and the raising and lowering is faster now after the fluid exchange. I have been able to move one mark closer to Sport on my shock setting without any additional ride harshness which I also credit to the fluid change.
My rig rides great, and the raising and lowering is faster now after the fluid exchange. I have been able to move one mark closer to Sport on my shock setting without any additional ride harshness which I also credit to the fluid change.
Just replaced the AHC fluud on mine. @PADDO thank you sir!
My fluid came out all dark and murky and I believe this is the first ever service at 241,000 miles.
All the bleeding nipples opened easily eventhough the truck has a ton of rust.
Now the height adjustments are much quicker but the ride is still as crashy as ever. I suspect my globes are shot. oh well at least I tried to fix AHC. Perhaps it is ti.e to switch to conventional setup
My fluid came out all dark and murky and I believe this is the first ever service at 241,000 miles.
All the bleeding nipples opened easily eventhough the truck has a ton of rust.
Now the height adjustments are much quicker but the ride is still as crashy as ever. I suspect my globes are shot. oh well at least I tried to fix AHC. Perhaps it is ti.e to switch to conventional setup
Does fluid degradation cause globe failures or is that a separate isssue? That’s quite impressive service ok original fluid!
I am sure fluid quality has an impact on the globe life. I am also curious as to what makes the old fluid go dark? The system is a closed one so there shouldn't be any external factors and I don't think it ever gets heated so any degradation probably comes from age and ambient temperature changes.
I’d suggest what contributes to fluid darkening with time and use is mostly due to oxidation and contact with the carbon black added to the rubber damper accumulator diaphragms and flexible lines. There will always be particulate material slough off the black colored system internals, you can easily see it collect in the pump internal filters and pump housing body. Also, as fluid ages its cocktail of additives including anti wear, anti foaming, anti rust, anti oxidation, pink dye and viscosity index stabilizers deplete which will also contribute to darkening and allow the gradual production of a dark sludge to form in solution. Moisture and air naturally in the fluid (there’s always trace moisture and air in hydraulic fluid) facilitate cloudiness, the formation of sludge, changes to pH and darkening with time and use too.
Technically the system’s design is open loop, not closed, with the reservoir open to atmosphere (the cap isn’t air tight and you have an air/fluid boundary) and, importantly for the definition, the pump draws from the same reservoir where fluid is also returned. The damping process actually produces quite a lot of heat at the damper assemblies. Don’t forget that the fluid is not only a working fluid for hydraulic lifting and leveling it’s also a shock fluid transferring energy (heat) in the damper valves. Have you noticed the cast steel cooling fins on the damper assemblies? they are there to increase surface area and dissipate heat.
Have you had a look at the 200’s system? Did they make some improvements? What are your thoughts on that system from a durability and reliability standpoint?
So about 50 miles later the suspension is becoming more compliant. Bouncing is almost gone and small road imperfections are not as noticeable.
I now wonder if a second flush will make it even better!
I now wonder if a second flush will make it even better!
does this work for LX570? the placement of the components in the diagram look different than the 200 series.
When I set it to low, does that go all the way to the bump stops, or is there a little bit more room left to descend when the fluid comes out? Just curious if I should expect the vehicle to settle lower than the "low" setting at any point in this process. I'm pretty slim and I'm trying to figure out if I can squeeze under there without going crunch. I'll have a spotter and a jack handy of course.
trdcorolla
SILVER Star
No, it get's a lot lower during the bleed. Don't get under the vehicle during the bleed. Once your ready to open the bleeder, slide back out then open the bleeder and the car will start lowering. I would get your pressure's in line before doing this. Some people got a few more grads from the globes after a pressure adjustment and a fluid flush, I didn't.
Ok thanks. I didn't have a good mental image of where all the bleeders are yet, so I wasn't sure if I had to be underneath or not.
trdcorolla
SILVER Star
Your replied to my post before I updated it. I added a note about pressure/grads.
You mean just check techstream for the AHC pressures? I've pulled up the AHC stuff but I have no idea what I'm really looking at. Or the reservour? I know that when I bought my 01 LX, I got between 9-10 tick marks on the reservoir b/w high and low.
trdcorolla
SILVER Star
Yup, check/adjust the pressures you see in Techstream. I learned how to look/adjust the torsion bars in another thread. It's easy peasy, if you already have tools, all you need to buy is the 30mm 6 point socket.
You can adjust AHC pressures in techstream? Interesting. You have a thread I can read up on that for? I have the FSM for my LX, but admittedly I've never looked in the AHC section
trdcorolla
SILVER Star
No, I wish. You read the pressure in techstream then you use the 30mm socket to adjust. Here is thread: Definitive list of AHC maintenance itemsYou can adjust AHC pressures in techstream? Interesting. You have a thread I can read up on that for? I have the FSM for my LX, but admittedly I've never looked in the AHC section
If I'm raising to neutral and then draining a little bit out of the passenger side F/R globes (as in step 9 on page one of this thread), wouldn't it shoot out at really high pressure and quickly drain? Or am I not thinking about this correctly.
Also, how tight should I twist the nipples?
Seems like they hold back a lot of pressure but I'd hate to over-torque one.
Also, how tight should I twist the nipples?
Seems like they hold back a lot of pressure but I'd hate to over-torque one.
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Like a woman, just enough to make her wince, but not enough to.... Aw crap, I'd better shut up before I get in trouble
Right when it was getting interesting too...
