ACH fluid bleed and status update

[Bunga]

Quick update. At 80k miles I did a 4 bleeder drain of the ACH, previous owner (and dealer) had never changed it. It was blackish with small dark particles. After changing, it rode vastly better and had much faster rise and (maybe) drop times.

After 30k I was starting to feel it get porpoisey, and even too soft at firm, and was considering new globes. But first I did the re-bleed and the color still looks great, still pinkish, no visible particles. But lots of bubbles on the RR and LF. Bled to no bubbles and now it feels great again. I would definitely bleed it at 25k next time.

I have the old stock ACH fluid so no risk of the mystery failure that the other threads are discussing.

 

[tbisaacs]

If you are seeing bubbles in the fluid that might indicate failed accumulators.

 

[Bunga]

Agreed, good thought. I'll drive it a week and see if they didn't have any bubbles or if they were the same as pre-bleed.

 

[pvchaitanya]

any good video on how to bleed AHC on lx 570 2011? I saw a couple of bleeder valves but also saw in forums with ppl having issues with AHC working again after bleeding or may be they did a flush.

So, if there is a simple safe procedure to just bleed the AHC fluid, please point me to the instructions of video.

 

[highfructose]

If you are seeing bubbles in the fluid that might indicate failed accumulators.

What should the fluid look like when it’s been bled to the appropriate degree?

Foamy like a freshly poured Guinness before it settles?

Bubbles like on the side of a glass of sprite down the tube?

Zero foam or bubbles whatsoever?

 

[aubie]

@pvchaitanya, Here's a good set of instructions from another thread. Fairly straight-forward procedure...just tedious and repetitive. I didn't notice much of a difference in ride quality as others have experienced but my fluid reservoir was running pretty low and the fluid that first came out of the accumulators was tan and milky. For those reasons, I was glad I did it and thought it was worth the hassle.

After talking to my service advisor at Lexus during my last oil change, I didn't get the impression they perform many AHC flushes. That and the contaminated fluid issue was motivation enough for me to give it a go. If you've ever bled brakes before...it's essentially the same process. McGeorge Toyota in VA still sells the old AHC fluid in 2.5L metal jugs (supposedly pre-contamination). I poured mine into a glass jar then into the reservoir each time just to be sure.

 

[aubie]

@pvchaitanya, nevermind...just saw your post was from a while back and it looks like you've already swapped your AHC fluid.

@highfructose here's what mine looked like after 4-5 trips at each accumulator. Not quite as good as original but at least it's red. New fluid is pink and my old fluid looked like muddy water at first.

 

[kwelhand]

@pvchaitanya, Here's a good set of instructions from another thread. Fairly straight-forward procedure...just tedious and repetitive. I didn't notice much of a difference in ride quality as others have experienced but my fluid reservoir was running pretty low and the fluid that first came out of the accumulators was tan and milky. For those reasons, I was glad I did it and thought it was worth the hassle.

After talking to my service advisor at Lexus during my last oil change, I didn't get the impression they perform many AHC flushes. That and the contaminated fluid issue was motivation enough for me to give it a go. If you've ever bled brakes before...it's essentially the same process. McGeorge Toyota in VA still sells the old AHC fluid in 2.5L metal jugs (supposedly pre-contamination). I poured mine into a glass jar then into the reservoir each time just to be sure.

Yeah, totally agree... I wouldn't let my local Lexus dealers touch my AHC.
One dealer doesn't know if we have an air or hydraulic suspension and other dealer told me that they only did 2 (two) AHC flushes for the entire calendar year... yikes~

 

[32cls6speedmt]

@aubie thanks for the write up and photo. How many miles on your LX?

 

[aubie]

@32cls6speedmt, not my writeup but I found it very helpful when I did my AHC flush. Glad to share the pic...probably should have taken more! I have just shy of 117k on my 09 LX. No record of it ever being done before.

I'm coming up on the big 120k service interval and fully intended on having Lexus do it, but it scared me when my last service advisor knew so little about the system, contaminated fluid, etc. Then I started pricing out what it would cost me to do the fluid exchanges. Even with premium fluids (Amsoil) there's quite a bit of savings and most are relatively easy to accomplish. Next up is F/R diffs, transfer case & tranny flush. Wanted to start with AHC and build a little confidence. I swore I was done doing my own maintenance when I bought my LX, yet here I am!!!

I guess I justify it with the thought: "who's going to take better care of my car than me?" IMO there's not a better vehicle than the 200 series and I want to keep mine on the road forever!!!!!!!!!!!!!