LX570 AHC “Basics” - Added as sticky thread for AHC Issues (11 Viewers)

[paulunm]

Thanks! I will do both, dealership here I come, my long time mechanic will not touch the hydraulic suspension

If your shocks aren't leaking, I wouldn't replace personally...

Also doing accumulators at a dealer will be hella expensive- like thousands I believe. I'd DIY it if I were you, maybe a local will help you out- it's not that bad of a job. Most difficult part for me (with a coach showing me what to do ) was getting the AHC guards off.

 

[lx200inAR]

Thanks! I will do both, dealership here I come, my long time mechanic will not touch the hydraulic suspension

If your shocks aren't leaking, I wouldn't replace personally...

Also doing accumulators at a dealer will be hella expensive- like thousands I believe. I'd DIY it if I were you, maybe a local will help you out- it's not that bad of a job. Most difficult part for me (with a coach showing me what to do ) was getting the AHC guards off.

Like @paulunm said, the globes MSRP is around $900 a peice and around $650 each from the discount lexus parts dealers. They can be ordered from Japan for about $500 for the set of 4 (via eBay or directly).

So get ready for the dealer to ask about $4k - $5k to do the swap. Or as stated, you can do it in your driveway in an afternoon for about $500 in globes and $100 in fresh AHC fluid.

If your shocks aren't leaking, no reason to swap them really. But, the shocks themselves are pretty cheap, labor to replace them might be a bit more. So if you just want to get it all done in one shot, it's not the worst idea.

 

[chriscosta416]

Can anyone post pics of the AHC data list from techstream who is running a non-modified AHC setup? I am trying to get my front leveled out but from a combination of messing with sensors a while back before knowing about height offset utility in techstream my data values are all over the place

 

[paulunm]

Can anyone post pics of the AHC data list from techstream who is running a non-modified AHC setup? I am trying to get my front leveled out but from a combination of messing with sensors a while back before knowing about height offset utility in techstream my data values are all over the place

The screenshot we took of mine not enough? You're welcome to re-connect to mine again if you like.

 

[JR YORK]

Thanks for the post, Longranger. I like the idea. I've had AHC-equipped LXs for almost 14 years now and have not had one AHC-related problem and I do not cruise malls - I use the heck out of my trucks.

That said, I do ensure I follow the maintenance schedule for AHC service. I do the flushes myself and they are not any more difficult than a brake system bleed, which I also do according to The Book. That's probably the only post-purchase preventive maintenance that is necessary.

In the spirit of creating a repository, below I pasted a comment I posted elsewhere a while back regarding why I think AHC is just fine. It may contribute to the value of this repository if someone is trying to decide if they should avoid AHC...

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So I'm going to throw in my two cents: "It's all about the requirements". The question regarding which suspension system is better can't be answered without first addressing what the truck will be required to do, for how long, and at what cost. The obvious extreme is the racing example. The system must perform at high speeds in very challenging conditions only long enough to win, and cost is not a limiting factor.

In the passenger market, the design-to conditions are less challenging, the system has to last 25(?) years, and the cost has to be competitive. Toyota has assessed, at least for now, that the LC market requirements are best answered with KDSS and the LX market with the AHC.

If you back into it, I think you'll find that both systems are perfect for a certain set of requirements. For example, here is why the AHC has been perfect for me for the past 14 years:

-- We do five or six long trips a year. Comfort is important on the way to whatever we will be doing, whether it is visiting family for Christmas, or four-wheeling into Park County.
-- We tow a 6000 lb boat and a 3000 lb enclosed trailer. Self-leveling and variable damping is important.
-- We need to get to mountain biking and hiking trailheads, hunting spots, and medium-difficulty off-road trails and raising the truck often mitigates risk of damage.
-- We have older parents who appreciate ease of entry when the truck is down.
-- We carry cargo now and again and I appreciate a lower truck when I am lifting something heavy in or out.
-- Back to towing: I am spoiled in that I can save time cranking the trailers up and down to ball level by raising and lowering the truck instead.
-- We hate washboard...and AHC almost eliminates it!
-- I do my own preventive maintenance and don't mind flushing the AHC according to the Toyota schedule.
-- We don't drive high-speed off road.
-- We don't purposefully leave the ground(!)
-- We don't rock crawl
-- I may get the itch once or twice a year, but I probably won't ever put sliders on my 570
-- *** The fact that I can't put Slee bumpers front and back and still maintain my stock cargo and towing capacity doesn't bother me a whole lot...just a little. Well, more than a little, but I've traded away that requirement and can live with it.
-- If it ever does fail, the chances are exceedingly low that I will be somewhere very far off road.

Bottom Line: For my requirements, AHC is perfect and Toyota's execution has been perfectly reliable and effective on both my '00 LX 470 and '11 LX 570.

Well put. The good news is that Slee does make bumpers for the LX570 now

 

[turbotwo]

Quick question, I see in the FSM that replacing the suspension control ecu requires me to run the height offset calibration in techstream. Will the vehicle be undriveable prior to doing this, or do I simply risk having a suspension lean one way or another? I ask because I still have a persistent C1755 code, and I sourced a used suspension control ecu which I'm hoping will sort out the issue. I also need new tires, so I'm hoping I can sort out the suspension, and then get new tires/alignment/suspension adjustments all done at once with functioning AHC.

 

[chriscosta416]

Hi all, I noticed my truck tends to lower itself a bit in the rear when parked, upon starting the truck the pump kicks on and raises it back to the N height I set it to (1 inch over stock) and it reliably stays at the correct height when driving.

Truck is not in easy exit mode.

Is this a sign of worn coils? New fluid and globes in the past 10k miles.

I also have coil spacers I can add to help alleviate AHC pressures.

 

[tbisaacs]

Hi all, I noticed my truck tends to lower itself a bit in the rear when parked, upon starting the truck the pump kicks on and raises it back to the N height I set it to (1 inch over stock) and it reliably stays at the correct height when driving.

Truck is not in easy exit mode.

Is this a sign of worn coils? New fluid and globes in the past 10k miles.

I also have coil spacers I can add to help alleviate AHC pressures.

Mine does this a lot and chocked it up to just normal self leveling. Similar to what happens at a stop light.

 

[TeCKis300]

Hi all, I noticed my truck tends to lower itself a bit in the rear when parked, upon starting the truck the pump kicks on and raises it back to the N height I set it to (1 inch over stock) and it reliably stays at the correct height when driving.

Truck is not in easy exit mode.

Is this a sign of worn coils? New fluid and globes in the past 10k miles.

I also have coil spacers I can add to help alleviate AHC pressures.

Agreed with @tbisaacs . It's not an indication.

The system is responding to height. As a result so unloading or people stepping out of the car when parking.

Same when starting the car, as it is responding to load or people added to the car.

Trust the system - it works and is robust.

 

[chapba]

Apologies if I overlooked it earlier in this thread, but is there a consensus on the best place to source AHC fuid?

Just got mine from jdmplanet on eBay shipped. Will be doing my swap asap. The link is on this thread…….somewhere…..

 

[fj60eric]

I was able to source mine at the local Toyota dealer, however I had to pick it up in person as I guess they aren’t shipping it anymore

 

[steveni70]

I was getting ready to do a sensor lift the other day when I noticed my front right sensor assembly was bent. I bent it back to approximately its original position, but I have no idea how or when it happened. It’s a 2014 that I bought in January. Any ideas on what could have caused this?

 

[chapba]

I was getting ready to do a sensor lift the other day when I noticed my front right sensor assembly was bent. I bent it back to approximately its original position, but I have no idea how or when it happened. It’s a 2014 that I bought in January. Any ideas on what could have caused this?

View attachment 3429257

Holy carp! Had to look at mine to see how tweaked your bracket is! Looks like it was pulled downward somehow. Somewhere amongst this thread or another is someone who fabricated a longer bracket to increase the sensor lift. Might look into that unless it’s not an issue after fixing it?

 

[eXpLoreLX]

Hey y’all I debated putting this question in “Stupid Question of the Day” or here in all thing AHC.

I decided here since maybe other have consider partial bleeding too

I have a 2018 LX that’s got bit of a judder or “looseness” or what feels like an under dampened shock on the rear axle. I currently have one 2.5 liter can of a AHC fluid and I’m wondering if I can safely and effectively just bleed the two rear circuits/shocks because I don’t know if I have enough for all four corners.

Or if that’s a waste of time if I don’t bleed all 4 at the same time.

Thoughts on just bleeding the rear to see if my jittery/juddery feel is from a little air in the system?

 

[Daniel11]

Peut-être les sphères qui sont HS si il le vehicule saute de l'arrière

 

[eXpLoreLX]

Peut-être les sphères qui sont HS si il le vehicule saute de l'arrière

Google translate isn’t perfect, but yes I agree that I might have a globe that is not functioning properly. Replacement of the globes wouldn’t be the first step though, so bleeding is up first. I’ve already ordered another can of AHC fluid, but I have some time right now and wondered if bleeding only the rear is a fools errand and a waste of time or if the circuits are separated enough that bleeding only the rear (where the perceived problem is felt) is a useful step.

 

[trudd]

Hey y’all I debated putting this question in “Stupid Question of the Day” or here in all thing AHC.

I decided here since maybe other have consider partial bleeding too

I have a 2018 LX that’s got bit of a judder or “looseness” or what feels like an under dampened shock on the rear axle. I currently have one 2.5 liter can of a AHC fluid and I’m wondering if I can safely and effectively just bleed the two rear circuits/shocks because I don’t know if I have enough for all four corners.

Or if that’s a waste of time if I don’t bleed all 4 at the same time.

Thoughts on just bleeding the rear to see if my jittery/juddery feel is from a little air in the system?

Depends on how much you plan on bleeding.

For a full proper flush, wait on the 2nd can to arrive. You'll need it. The last thing you want to do is add a lot of new fluid now without bleeding out all of the old fluid. The new and old fluid will get mixed back in together and you'll have to start from square 1 for a proper flush next time.

If you just want to check for bubbles, bleed the rears now and put that fluid back into the reservoir (so long as its free of contaminants). If you haven't done a bleed/flush before, this will help you get used to the process when the big day comes.

 

[eXpLoreLX]

Depends on how much you plan on bleeding.

For a full proper flush, wait on the 2nd can to arrive. You'll need it. The last thing you want to do is add a lot of new fluid now without bleeding out all of the old fluid. The new and old fluid will get mixed back in together and you'll have to start from square 1 for a proper flush next time.

If you just want to check for bubbles, bleed the rears now and put that fluid back into the reservoir (so long as its free of contaminants). If you haven't done a bleed/flush before, this will help you get used to the process when the big day comes.

Okay, I’ll wait for my extra can to show up.

I had a local shop install the Wescott spacers and bleed the system but they only used one can of fluid.

I’ve been a bit suspicious for awhile that the system was not fully bled out and that my rear axel symptoms may be related to air that got in during disconnecting and reconnecting the shocks.

If that doesn’t fix the problem I guess the next step is new globes.

 

[lx200inAR]

Okay, I’ll wait for my extra can to show up.

I had a local shop install the Wescott spacers and bleed the system but they only used one can of fluid.

I’ve been a bit suspicious for awhile that the system was not fully bled out and that my rear axel symptoms may be related to air that got in during disconnecting and reconnecting the shocks.

If that doesn’t fix the problem I guess the next step is new globes.

Did your westcott set up come with any sort of lift? If you raised the rear at all you may just be feeling the affects of sagitta in the new geometry of the panhard bar.

 

[eXpLoreLX]

Did your westcott set up come with any sort of lift? If you raised the rear at all you may just be feeling the affects of sagitta in the new geometry of the panhard bar.

Theoretically the Westcott kit shouldn’t actually provide lift. It’s more like a preload collar. The actual lift comes from adjusting the sensors. I’m at max sensor lift without any modification to the sensor arms.

But this is not a geometry thing it almost feels like something is loose but I’ve had all the bushings inspected and all the bolts double checked.

A Second off-road shop diagnosed as “I need my suspension tuned”. But obviously that’s not a real option on the AHC system. I haven’t heard others mention that jittery or loose feeling after doing Westcotts (or other spacers) and suspension sensor lift. Obviously I can’t rule it out, but at the moment the current scenario looks like air in the hydraulic line or a bad globe that isn’t properly dampening in small ripple type bumps and allows for a bit of a loose and bouncy feel.