LX570 AHC Globe/Accumulator Replacement (10 Viewers)

[grinchy]

There is something in how ifs and solid axle interact to the ahc design.
Just based on how my truck reacts to front weight vs rear weight. I also think this is why the design is more elaborate for the fronts.

 

[lx200inAR]

There is something in how ifs and solid axle interact to the ahc design.
Just based on how my truck reacts to front weight vs rear weight. I also think this is why the design is more elaborate for the fronts.

I suspect there are certainly some differences, but on the 300 series the rear axle gets the more elaborate design as well.

 

[TeCKis300]

I wouldn't get too caught up in the specific pressures. It's setup for the system and I'll caution more is not always better.

There’s some math there I’m having trouble wrapping my head around.

The higher spring rate No2 chambers also have a lower charge pressure . It is also a smaller volume.

I assume there is something I’m not wrapping my head around that the lower charged gas spring makes for a higher spring rate. The only thing off my dome I could come up with is that the spring would be activated at a lower pressure, so possibly that’s why it creates a higher spring rate.

If I'm understanding...

The front being IFS has a different motion ratio because of architecture and shock placement. There is much less travel in the front shock which is almost 2:1. Which is why the front accumulators are charged higher. Rear shocks are much closer to 1:1.

Accumulators also work differently and initial install, or pre-charged pressure, doesn't really mean much other than setup. Because it ultimately will be working at the system pressure. Smaller volume accumulators also increase in rate quicker so it works as the progressive high-rate spring.

 

[AnyMal]

There’s some math there I’m having trouble wrapping my head around.

The higher spring rate No2 chambers also have a lower charge pressure . It is also a smaller volume.

I assume there is something I’m not wrapping my head around that the lower charged gas spring makes for a higher spring rate. The only thing off my dome I could come up with is that the spring would be activated at a lower pressure, so possibly that’s why it creates a higher spring rate.

I didn’t even try to wrap my head around your original post and barely skimmed it

Make it make sense, I personally dont get the rear. It barely has any coil spring / strong rate back there. And one less stage of valving control / relief solenoid?
The discrepancy has got to be something with the cross link, where it shares the load (samwise gamgee) with the front stage 2 or something to compensate. Im literally spitballing here and wiped out from my install. Sorry.

I was also wondering in another thread about using the gx bags AS the rear coils, and i bet you its entirely possible. Ive man handled those coils, by hand, no way the GX bags cant handle that LX rear load. The rear are slinky as f.

 

[LEXCRUISER]

Can I replace just 1 accumulator?

 

[grinchy]

Can I replace just 1 accumulator?

If you have a way to test and the others test good, I see no reason you couldn’t replace just the bad one(s).

 

[LEXCRUISER]

If you have a way to test and the others test good, I see no reason you couldn’t replace just the bad one(s).

The rear passenger AHC accumulator hits rock and started leak. We were about 35-40 miles out to pavement. So, when this happened, the goal is to get out of the trail safely. I managed to drive over 100 miles home. The rear dropped low and front is still ok. So, I have all 4 accumulators, but was thinking to just replaced the damaged accumulator. The car is currently 88000 miles.

 

[grinchy]

The rear passenger AHC accumulator hits rock and started leak. We were about 35-40 miles out to pavement. So, when this happened, the goal is to get out of the trail safely. I managed to drive over 100 miles home. The rear dropped low and front is still ok. So, I have all 4 accumulators, but was thinking to just replaced the damaged accumulator. The car is currently 88000 miles.

Yeah, that’s a good use case for swapping one, but if you already have the other rear in hand I’d do the pair.

 

[LEXCRUISER]

Yeah, that’s a good use case for swapping one, but if you already have the other rear in hand I’d do the pair.

Is the procedure still the same? Bleed the accumulator and remove. Then, install the new one?
Should I replaced both rear accumulator before restarting the car?
Thanks in advanced

 

[grinchy]

Go to low mode.
pull the accumulator skid bars.

Repeat for each corner:
Unscrew the accumulator.
Prefill the new one (a few teaspoons)
Screw on the new one

Then a full four corner bleed, throw in the fifth location at the solenoid for bonus points.

There’s a few full accounts in various threads, including my build theead
Post in thread 'The Guzzler - 2009 LX570'
Builds - The Guzzler - 2009 LX570 - https://forum.ih8mud.com/threads/the-guzzler-2009-lx570.1052021/post-12948642

 

[lx200inAR]

Go to low mode.
pull the accumulator skid bars.

Repeat for each corner:
Unscrew the accumulator.
Prefill the new one (a few teaspoons)
Screw on the new one

Then a full four corner bleed, throw in the fifth location at the solenoid for bonus points.

There’s a few full accounts in various threads, including my build theead
Post in thread 'The Guzzler - 2009 LX570'
Builds - The Guzzler - 2009 LX570 - https://forum.ih8mud.com/threads/the-guzzler-2009-lx570.1052021/post-12948642

The 5th accumulator is sealed from system except during a lift. Not really any reason to bleed it if you are t trying to get the fluid out of it.

Taking that thought further, for poos and giggles, the accumulator is charged with quite a bit of pressure (around 900 PSI I believe). Making it almost impossible for air to end up in it in any scenario.

 

[Stjohnvalley]

Hope this is a good spot to add my experience. This forum has been so helpful i feel i should add to the knowledge pool if i may. I have a 08 Lx 570 with 180k on it. I have been putting off AHC maintenance other than a flush when i bought it a couple yrs ago with 140k on it. Well the other night on the way home in a snowstorm the AFS headlight warning came on and the rig seemed to be riding low in the front. Basically no suspension at all. Then the check 4 wheel AHC light showed up. Ugg its dark and the kids are complaining that we cant go over 15 mph. Thankfully we made it home. After a inspection the fluid looked good no leaks and the tank was full but the rear end was at normal height and the front was down on the stops. ??? What in the world. I ordered new globes and fresh AHC fluid but nothing added up after spend hours reading forums here. Well i jacked up the front, i was afraid to start it yet. After inspecting the front closer now the culprit is discovered. The front driver side hight sensor had broken off the upper control arm and was hanging free. The little link with 2 ball joints on it had broke the steel piece that was welded to the arm. The upper ball joint had rusted or frozen in place and over time fatigued the steel till it actually broke! Curse the salt in Maine. So everyone who lives in the north may want to check their front height sensors and make sure they move as they should. I hope this helps someone catch a potential issue before something terrible happens. I shudder to think what would have happened if we were cruising 80 on the interstate. Cheers

 

[Stjohnvalley]

Hope this is a good spot to add my experience. This forum has been so helpful i feel i should add to the knowledge pool if i may. I have a 08 Lx 570 with 180k on it. I have been putting off AHC maintenance other than a flush when i bought it a couple yrs ago with 140k on it. Well the other night on the way home in a snowstorm the AFS headlight warning came on and the rig seemed to be riding low in the front. Basically no suspension at all. Then the check 4 wheel AHC light showed up. Ugg its dark and the kids are complaining that we cant go over 15 mph. Thankfully we made it home. After a inspection the fluid looked good no leaks and the tank was full but the rear end was at normal height and the front was down on the stops. ??? What in the world. I ordered new globes and fresh AHC fluid but nothing added up after spend hours reading forums here. Well i jacked up the front, i was afraid to start it yet. After inspecting the front closer now the culprit is discovered. The front driver side hight sensor had broken off the upper control arm and was hanging free. The little link with 2 ball joints on it had broke the steel piece that was welded to the arm. The upper ball joint had rusted or frozen in place and over time fatigued the steel till it actually broke! Curse the salt in Maine. So everyone who lives in the north may want to check their front height sensors and make sure they move as they should. I hope this helps someone catch a potential issue before something terrible happens. I shudder to think what would have happened if we were cruising 80 on the interstate. CheersView attachment 3212995View attachment 3212996

Oh yea the headlight warning was because the angle was too steep in the front and they couldnt level.

 

[PDoyle]

You just gotta get under it more often

 

[KRR]

Hi all,

I have another question regarding the AHC system on the 200 series/LX. Just this morning i circulated the AHC from Low to High and back to Low again. I noticed that there was oil dripping down from the rear right fender where the reservoir is located. Seems that it's dripping from the overflow pipe. I noticed when in N (Normal/Neutral) position the oil is right where its supposed to be in the middle. Could it be that previously it was overfilled, or is there still air in the system? Thanks guys

 

[TeCKis300]

Hi all,

I have another question regarding the AHC system on the 200 series/LX. Just this morning i circulated the AHC from Low to High and back to Low again. I noticed that there was oil dripping down from the rear right fender where the reservoir is located. Seems that it's dripping from the overflow pipe. I noticed when in N (Normal/Neutral) position the oil is right where its supposed to be in the middle. Could it be that previously it was overfilled, or is there still air in the system? Thanks guys

Is your AHC system modified?

Couple potential reasons
1) Yes, overfilled
2) Too much spring rate (due to modification), that the accumulators are evacuating a large part of their fluid in order to reach low. This can cause the reservoir to overflow.

 

[trudd]

Well, after sitting on my replacement globes for 9 months, I finally replaced them today. And boy, I wish I had done it sooner. 2009 LX w/ 164k miles on the clock. I've owned it for 2.5 years, since 137k.

I discovered a total failure of my rear driver-side globe.

I did a visual check on removal and could see the metal diaphragm on the first 3 globes. On the last one, it was a black hole. So I grabbed a pencil and could feel the collapsed diaphragm on the bottom of the globe. Wow. Take a look at the red circled reference mark. It was nothing more than a bowl full of AHC soup.

As it goes, the car now rides like a dream. I had previously replaced the fluid last summer, which helped the ride a bit. I had no idea what I was missing. It eats up the bounces when driving over the nearby railroad tracks. I'm not exactly sure when the diaphragm collapsed, but the ride quality has certainly degraded casually over the last ~5 months.

Other notes from the job:

• the rear passenger globe spewed AHC fluid everywhere upon removal, despite being double bled per @baktasht 's video. It was the only globe that did that.
• definitely get the 6-sided 21mm socket. Even then, I nearly stripped the bolt on the last globe. So glad I didn't use a 12-sided socket.
• Going from Low to Neutral is taking a long time. 30+ seconds long. N to H is quick. Previously L to N was a fast process. Hopefully this speeds up over time.
• even my wife noticed the ride difference.

I can't thank @baktasht enough for his videos! His Redarc brake controller installation video was equally helpful. And thanks to everyone else for sharing their experiences. I'm not a mechanic by any means, but I got to play the part today!

 

[04UZJ100]

Well, after sitting on my replacement globes for 9 months, I finally replaced them today. And boy, I wish I had done it sooner. 2009 LX w/ 164k miles on the clock. I've owned it for 2.5 years, since 137k.

I discovered a total failure of my rear driver-side globe.

I did a visual check on removal and could see the metal diaphragm on the first 3 globes. On the last one, it was a black hole. So I grabbed a pencil and could feel the collapsed diaphragm on the bottom of the globe. Wow. Take a look at the red circled reference mark. It was nothing more than a bowl full of AHC soup.

View attachment 3264300

As it goes, the car now rides like a dream. I had previously replaced the fluid last summer, which helped the ride a bit. I had no idea what I was missing. It eats up the bounces when driving over the nearby railroad tracks. I'm not exactly sure when the diaphragm collapsed, but the ride quality has certainly degraded casually over the last ~5 months.

Other notes from the job:

• the rear passenger globe spewed AHC fluid everywhere upon removal, despite being double bled per @baktasht 's video. It was the only globe that did that.
• definitely get the 6-sided 21mm socket. Even then, I nearly stripped the bolt on the last globe. So glad I didn't use a 12-sided socket.
• Going from Low to Neutral is taking a long time. 30+ seconds long. N to H is quick. Previously L to N was a fast process. Hopefully this speeds up over time.
• even my wife noticed the ride difference.

I can't thank @baktasht enough for his videos! His Redarc brake controller installation video was equally helpful. And thanks to everyone else for sharing their experiences. I'm not a mechanic by any means, but I got to play the part today!

A high quality set of pliers (Knipex Cobras) made mince-meat of removing the globes too.

Glad to hear yours is riding better. It's such an easy job that so many dealers royally **** up.

 

[NKP Garage]

Well, after sitting on my replacement globes for 9 months, I finally replaced them today. And boy, I wish I had done it sooner. 2009 LX w/ 164k miles on the clock. I've owned it for 2.5 years, since 137k.

I discovered a total failure of my rear driver-side globe.

I did a visual check on removal and could see the metal diaphragm on the first 3 globes. On the last one, it was a black hole. So I grabbed a pencil and could feel the collapsed diaphragm on the bottom of the globe. Wow. Take a look at the red circled reference mark. It was nothing more than a bowl full of AHC soup.

View attachment 3264300

As it goes, the car now rides like a dream. I had previously replaced the fluid last summer, which helped the ride a bit. I had no idea what I was missing. It eats up the bounces when driving over the nearby railroad tracks. I'm not exactly sure when the diaphragm collapsed, but the ride quality has certainly degraded casually over the last ~5 months.

Other notes from the job:

• the rear passenger globe spewed AHC fluid everywhere upon removal, despite being double bled per @baktasht 's video. It was the only globe that did that.
• definitely get the 6-sided 21mm socket. Even then, I nearly stripped the bolt on the last globe. So glad I didn't use a 12-sided socket.
• Going from Low to Neutral is taking a long time. 30+ seconds long. N to H is quick. Previously L to N was a fast process. Hopefully this speeds up over time.
• even my wife noticed the ride difference.

I can't thank @baktasht enough for his videos! His Redarc brake controller installation video was equally helpful. And thanks to everyone else for sharing their experiences. I'm not a mechanic by any means, but I got to play the part today!

You got it! I enjoy making the videos whenever I get time tinker. Glad it was helpful. And that Redarc brake controller is the best isn't it? I sold my LX570, but on the hunt for another one. Owned a crazy number of vehicles over the last 27yrs, and the LX570 has been by far my favorite.

 

[trudd]

Has anyone else had problems with intermittent ride quality after changing globes? I swear, it rode like a cloud for a day or so afterward, and is somewhat inconsistent now.

After it gets bouncy again, I bleed a little bit from each corner. Around an ounce at most. There have been a few small air bubbles, but nothing insane. Feels like it that made a difference one time, but again - it's inconsistent.

I cycled from N -> L -> H -> N once and some comfort felt restored. I'm not quite sure what to make of this.