Props to PADDO's AHC fluid replacement method! (2 Viewers)

[Mbchance]

Hey gang- new to the forum here. Just purchased a 2000 LX 470. Overall in good cosmetic and mechanical condition, but noticed the rear is leaning about 1" (rear passenger is about 1" lower than driver side). First looked into torsion bar adjust, but noticed the AHC levels are very low even in the L setting. My AHC does work even with low fluids- assuming there is enough in the lines to raise & lower. So first on the list will be an AHC flush with new fluids to FSM min/max.

The posted instructions seem pretty straight forward for DIY. I am a bit unclear on the bleeding- the diagram notes 5 areas with fluid bleeders (height control accumulator + 4 dampers), but the instructions only refer to bleeding on the LH side. I assume the LH is "left hand" or drivers side? As PADDO's method notes, both sides will lower when bleeding front & rear on LH side. Could someone clarify if bleeding is ALSO required on the RH right hand/passenger side?

*PADDO if you see this, I am also in Charlotte. Would love to connect! Send PM- I would rather pay for your expertise, especially since you are nearby- rather than me pissing away time & money from my newbie trial & error. So probably looking at torsion bar adjust or re-indexing after AHC fluids, would love some help.

Also- thanks to all the members for all the valuable input! This site has quickly become my "go to" resource for 100 series!

FYI, if you want to “tag” someone, put an @ sign before their name.
Secondly, yes, the LH side means drivers side and while you can bleed just that side, it’s recommended to bleed all corners to get fresh fluid into every accumulator.
When you begin, the first bleed will be the most and it will drop the system since both sides of the vehicle are hydraulicly connected. A quick open and close of the bleeders of the others will typically yield fresh fluid rather quickly unless your accumulators are shot. The key to bleeding AHC fluid is to make sure your reservoir never runs dry and you suck air into the system. All long as you don’t do that, you really can’t bleed to much. It’s just not worth it to waste more than needed.

 

[SouthSide]

@PADDO I am in Charlotte hit me on PM.

 

[r2550g]

Much thanks to @PADDO and all folks who have made this maintenance so clear and straightforward!! Just followed the procedure and got it done to my 07 LC. The fluid was a bit low when started so it took about 2.75 bottles of AHC fluid.

One quick question, how to check if there is any air trapped in the system? there was no air when I did the very last step on PS side, just fresh fluid came out when I loose the bleed screw.

Thanks again to all!

 

[looking4lc]

One quick question, how to check if there is any air trapped in the system? there was no air when I did the very last step on PS side, just fresh fluid came out when I loose the bleed screw.

Thanks again to all!

usually when u see bubble during bleeding in the hose, you let all out, once stopped, should be no air trapped.

 

[axle167]

It’s been a couple years since my last bleed. My last bleed has pink milkshake with an emulsion that settled in the bottle... see post 40’s

my latest bleed also gave me foamy fluid, however there was no emulsion after the foam was gone, fluid was dark tho.

after the bleed, I noticed that the ahc are self leveling more often while driving. Today, I noticed that the front end drops while parked and will self level when car starts. I checked the level in the reservoir and it looks fine, so I don’t think it’s leaking out... perhaps leaking back into the reservoir? Should I be worried?

 

[A LEXUS BLEDEL]

Just took care of this today thanks to @PADDO ! Have had this LX for over a year now and suspension worked fine but always seemed a bit harsh over bumps and slightly unstable in turns. Service records showed the AHC fluid was replaced at the dealer in 2013, so I figured it was about time.

Old fluid came out light green at first and then foamy black. Rear fluid was the worst, super dark and murky. Craziest part is when it takes about a minute to go to N when first rising with the new fluid and the N light keeps blinking. Eventually it made it there no problem and the suspension handles way better all around.

This is a definite must do for AHC owners before considering ditching the AHC for a traditional suspension. (Unless the globes are all shot of course)

Thanks @PADDO!

 

[ToywitaL]

I just had my AHC fluid replaced. My local indy shop quoted me over 3 hours labor. After reading many posts here that people were getting it done in an hour or less, I reached out to PADDO for advice. He provided me a step by step process that I gave to the local shop.

They ended up following his system and billed me 45 minutes of labor. They said they liked the process so much they are keeping the print out for future reference.

Thanks PADDO and MUD! I just can't say enough about PADDO's generosity, patience and willingness to share his knowledge with newbies like myself.

I'll leave it up to PADDO to bring his system to the masses.

PADDO First and foremost. Thank you all for the hard work. I for one appreciate it. 2005 GX fun/runner is totaled. Back to another LX. Yes! Al most as good as my 4Runner's switch to my F60-62`s. This ones a 1999, 168K, black with tan, gold sticker,and it sat a lot. Sun roof Ha. At least its closed. The pogo stick ride has got to go. 5.5 total AHC (Thank you for the helpfull info) used from top to bottom. All 3 modes LNH work but ride is no good. Lets see if the 4 used ebay globes will help. I had a 1998LX with 247k and the original AHC worked fine. Will try and get some pic`s on here. To help .

 

[shiretowndown]

Thanks Paddo! Any issues with swapping the bleeders as I work each corner? i.e. when the fluid stops flowing unscrew the old bleeder and install the new one?

So my modified procedure would look like this:

4. Starting at the height accumulator (12 inch long cylinder on DS outer frame rail, between front and rear damper assemblies) connect your drain tube, crack the bleeder and commence draining fluid, when fluid flow stops, remove and replace bleeder valve. You should drain ~0.3 liters.

5. Move to the front LH damper assembly, connect tube, crack the bleeder and drain until the front has dropped down to the bump stops. Both sides of the vehicle will lower together (because they are hydraulically connected) and you should drain ~0.4 liters. When fluid flow stops, remove and replace bleeder valve.

6. Same as 5 but at LH Rear

7. Making sure there is enough fluid in the reservoir, Bleed PS front valve and replace (should be a fairly small amount of fluid?).

8. After checking reservoir levels, Bleed PS Rear. Remove and replace valve (should be a fairly small amount of fluid?).

9. Start the vehicle, let it idle for 30-60 seconds and then press the UP button to raise to NORMAL height. The whole system will refill and recharge with new fluid from the reservoir and the level in the reservoir will be drawn down to slightly over the max line if everything has gone as expected.

10? Now would I have to go back and do quick bleeds on each side to get bubbles out because I Removed and replaced the valves or should it be ok?

11. You're done, confirm that the reservoir fluid level is correct - between max and min at N height with the engine running. There is nothing wrong with leaving the level slightly over the max line.

How many (total) replacement bleeder plugs would one need?

 

[shiretowndown]

It’s been a couple years since my last bleed. My last bleed has pink milkshake with an emulsion that settled in the bottle... see post 40’s

my latest bleed also gave me foamy fluid, however there was no emulsion after the foam was gone, fluid was dark tho.

after the bleed, I noticed that the ahc are self leveling more often while driving. Today, I noticed that the front end drops while parked and will self level when car starts. I checked the level in the reservoir and it looks fine, so I don’t think it’s leaking out... perhaps leaking back into the reservoir? Should I be worried?

Could this be a height sensor issue?

 

[uHu]

....after the bleed, I noticed that the ahc are self leveling more often while driving. Today, I noticed that the front end drops while parked and will self level when car starts. I checked the level in the reservoir and it looks fine, so I don’t think it’s leaking out... perhaps leaking back into the reservoir? Should I be worried?

Could this be a height sensor issue?

This is normal behaviour. The whole purpose of the ahc is that it's self levelling. Whenever there is a change in driving conditions (like speed, uphill, downhill), or weight distribution, the height will need to be "corrected". Typically, whenever you stop, it will change the height either front or rear, and this will differ according to the inclination of your parking place. Then if the back seat passenger leaves and closes the door, it will level again.
If you, when parking, turn off the ignition right away, it will not have time to level out, and then it will level out when you start again instead.

But yes, if a height sensor starts giving unreliable feedback, the height can change when it shouldn't. Also, the damping can get harsh if the ahc ecu thinks that the height is changing all the time (nervous sensor).

 

[shiretowndown]

You’ll be fine to replace the bleeders at each point as you’ve outlined. That’s what I’ve done, bleed, unscrew old and screw in new one. Don’t over tighten them, just firm them up and pop the rubber cap back on. I wouldn’t bother with Step 10 as long as you don’t wait forever to screw the new bleeder in. Probably wouldn’t hurt to check for any drips after you’ve recharged the system as the new bleeders might need a bit of encouragement (slightest tightening) to seat properly.

So just to verify, I can allow old AHC fluid to stop flowing from old bleeder screw, remove old screw/plug and replace with new OEM one and just snug up? As long as I keep my fluid level in resevoir topped off I should worry about air getting into system from the bleeder port?

Thanks for all the info on here, I am picking up my AHC fluid liters today from my Toyota dealer as well as new bleeder screws and caps.

- Garrett

 

[2001LC]

We've 4 globes bleeders and 1 accumulator bleeder, they're different. They also have different torque spec. Globes 73IN-lbf (Inch, not pound foot) Accumulator 62in-lbf.

 

[shiretowndown]

We've 4 globes bleeders and 1 accumulator bleeder, they're different. They also have different torque spec. Globes 73IN-lbf (Inch, not pound foot) Accumulator 62in-lbf.

So @2001LC are you saying the bleeder plugs are different for the (4) globe bleeders and the (1) accumulator bleeder?

Regarding their torque specs....I don't know that I'm going to go purchase a tool to ensure I hit those. Got any advice on what those torques feel like by hand?

 

[2001LC]

Yes different The one in the accumulator, @PADDO measured as thinner walled. It is the one most often busted if bleed cap is not used.

Sung, very very lightly. Then watch for leaks or weeps. If you see weeps, sung a little more. Or get yourself a $20 Harbor Fright 1/4" torque wrench.

 

[shiretowndown]

Dog!

what’s the Part# for that one then?

i just ordered 5 of these:

 

[2000LX4me]

Same, 5 screws 5 caps. lol just ordered as well from McGregor in a bigger order. palm to forehead. Need the "one" other part #.

 

[2001LC]

It's likely fine. They may not even sell different ones for accumulator, IDK. Just check that the old has same size and angle as new, at tip/seat.

 

[shiretowndown]

I’m beginning the PB Blaster pre-soak now. Looking to do the job once it’s Sunny and 62 on Friday. That’s excellent weather here in Roll Tide Land this time of year.

 

[2000LX4me]

1 hour job from moment I turned car on to lower to N til finished review of tank level.
2.4 litres via 1 litre bottles filled in.
Accumulator and LF .4 and ,3 as advertised. im sure LR as also .3 but the milk shake was too much for my 500mL bottle, heads up if small catch bottle will need to stop/start.
After small bleed on RH side as final step, fluid was a tad darker pink then out of the litre bottle, great stuff. I drained appox 200mL on RH side.
Reviewed level...impossible from front or even side due to staining. Best way was shine light from drivers side of resevoir right thru tank,... pink visible clearly right at the Max line. Thanks all.

 

[aharlan001]

Moved to new thread