AHC starting to go out pretty soon... suspension options? (1 Viewer)

[marcuslx470]

so I went ahead and went to Toyota to get a check-up on the LX today.

long story short, the mechanic mentioned that for having 300,000 miles on it, it was in very good condition top to bottom, except for one issue

he took me back to the back and had the truck on the lift. he showed me areas of it leaking (not major, but very minor) boots being torn and bearings a bit loose, but not too much for it to be a problem, at least for now. He recommended me to just go ahead and deactivate the system and go old school suspension. I realize the AHC is a complex and complicated system but sadly might go the cheaper route and replace it. I have looked through a few forums, so correct me please if I might have missed a few threads.

my current set up:
2002 LX470 with about 280,000 miles

- arb bumper
- front runner rack
- some gear for recovery and etc
- and I have future mods such as a rear tire carrier/ bumper in the near future
- I often tow as well, nothing too crazy.

1) what is the best kind of suspension to go? I heard slee was good but was open to hear others experiences as well. I enjoy a comfortable ride with something that's not so stiff and makes me feel every single bump on the road

2) would it be best to go for a medium load or heavy load springs? I'm not going to be going extra heavy with gear but maybe the bumpers and just as insurance get heavy? not sure what's considered overkill

3) I've seen people get kits and some include upper control arms and some don't. what exactly are y'alls opinion on pro's and con's of getting it or not getting it? is it that much of a difference?

I'm thankful for any replies in the right direction as I am not that experienced in the suspension area. and I do apologize if this sort of question has been answered somewhere else. I just can't seem to find a straight forward answer. attached is what the mechanic wrote down about the vehicle.

 

[suprarx7nut]

Hang on. First things first.

You have a torn ball joint boot (replaceable by itself, low $) and a low AHC reservoir. And the mechanic jumped straight to AHC replacement? That's insane.

The fact that he didn't mention pressures tells me he didn't test them. If he didn't test them, you have no idea what the pressures are and therefore, no idea if a simple adjustment will bring the system back to 100%.

If you have the ARB bumper, the torsion bars will need a serious, massive adjustment ($0 in parts, just some labor to turn a wrench) to get pressures back into spec, if that hasn't already been done.

I think you need to seek out somebody that's familiar with AHC and techstream and that knows how to do a basic diagnosis on AHC.

Your cheap option is very likely to test and adjust AHC. You do not need new suspension based on your post here and a complete replacement of the system is beyond overkill.

 

[saucebox]

1) what is the best kind of suspension to go? I heard slee was good but was open to hear others experiences as well. I enjoy a comfortable ride with something that's not so stiff and makes me feel every single bump on the road

2) would it be best to go for a medium load or heavy load springs? I'm not going to be going extra heavy with gear but maybe the bumpers and just as insurance get heavy? not sure what's considered overkill

3) I've seen people get kits and some include upper control arms and some don't. what exactly are y'alls opinion on pro's and con's of getting it or not getting it? is it that much of a difference?

I'm thankful for any replies in the right direction as I am not that experienced in the suspension area. and I do apologize if this sort of question has been answered somewhere else. I just can't seem to find a straight forward answer. attached is what the mechanic wrote down about the vehicle.

For the first—two answers. 1) Not a whole lot of detail in the leaks. If it's a single component or even a couple, it's likely far cheaper to replace those, and the ride/capabilities will stay the same. 2) Trail Tailor if you're set on an aftermarket kit. I have only the rear done (so far), and went with extra heavy because I've got the rear bumper, a full set of drawers, and a fridge always in the truck. Jason will set you up based on what gear you have or plan to have, and get the right kit to you (same is true for OME lifts at Cruiser Outfitters also, but I like the OME shocks less). I got my LX with an OME suspension already installed, and the difference is HUGE between the shocks. But it still rides like a truck, not like an LX with the AHC.

2—Trail Tailor and Cruiser Outfitters will both sort you out with the correct springs after a chat. You'll tell them what you have or are planning to have, and they'll suggest the right springs. Each pair is usually rated at +load, so if you're constantly 300lbs overweight, they'll match a spring meant for that load.

3) Don't know the answer. I went with SPCs right before Trail Tailor released his version. I'd probably do the UCAs (one and done), but the necessity probably depends as much on the rest of your components.

Long story short — get your system properly tested to see what the problem might be. Aftermarket is a huge expense for a ride that might not meet expectations.

Edit: @suprarx7nut beat me to it. It's cheap to diagnose and find the real problem.

 

[marcuslx470]

Hang on. First things first.

You have a torn ball joint boot (replaceable by itself, low $) and a low AHC reservoir. And the mechanic jumped straight to AHC replacement? That's insane.

The fact that he didn't mention pressures tells me he didn't test them. If he didn't test them, you have no idea what the pressures are and therefore, no idea if a simple adjustment will bring the system back to 100%.

If you have the ARB bumper, the torsion bars will need a serious, massive adjustment ($0 in parts, just some labor to turn a wrench) to get pressures back into spec, if that hasn't already been done.

I think you need to seek out somebody that's familiar with AHC and techstream and that knows how to do a basic diagnosis on AHC.

Your cheap option is very likely to test and adjust AHC. You do not need new suspension based on your post here and a complete replacement of the system is beyond overkill.

he did mention that the graduations are extremely low (less than 7 graduations from normal ride height) and he said that the rear main seal also leaks so even if i did try and fix it, id feels like the problem will just reoccur with another side. i know it sounds ridiculous him saying to just get rid of the entire system, but then again i think about costs trying to maintain it down the road sounds like an expensive fix here and there. and do you think if i do get it back to 100%, that i can have a chance of still using AHC while towing and with current/more gear in the future?

 

[nothappening]

Low graduations is a sign that the globes are losing their functionality. Globe replacements can be had new OEM for around $1350 for all four of them. It's a relatively straight forward job from what I've heard, I haven't done it myself.

Genuine question: What does the rear main seal have to do with the AHC?

Edit: I'm not even sure if it's a fair graduations test if you are low on fluid...

 

[marcuslx470]

Low graduations is a sign that the globes are losing their functionality. Globe replacements can be had new OEM for around $1350 for all four of them. It's a relatively straight forward job from what I've heard, I haven't done it myself.

Genuine question: What does the rear main seal have to do with the AHC?

he mentions and showed me spots where it was leaking minorly at 2 points, a reason why the graduations were becoming lower within the past few months.

 

[suprarx7nut]

he did mention that the graduations are extremely low (less than 7 graduations from normal ride height) and he said that the rear main seal also leaks so even if i did try and fix it, id feels like the problem will just reoccur with another side. i know it sounds ridiculous him saying to just get rid of the entire system, but then again i think about costs trying to maintain it down the road sounds like an expensive fix here and there. and do you think if i do get it back to 100%, that i can have a chance of still using AHC while towing and with current/more gear in the future?

If you are low on gradations, that means your globes (pressurized nitrogen balls) are worn out and need replacement. A full set is around $1000 and is basically the only expected wear item in the system. A full set of these is far cheaper than a comparable traditional shock set.

I don't know what the rear main seal is in this context. The "rear main seal" is the crankshaft seal between the engine and transmission. If he means something related to AHC, it probably just needs a new gasket or o-ring. It may be leaking because the system hasn't be adjusted to your added weight and is pressurizing more than normal to attempt to keep your rig at the desired height.

The expensive parts of AHC that have any likelihood of failure are the pump and globes. Your globes are worn and need replacement ( so it seems), but replacing all of them is cheaper than a traditional suspension swap with new, good parts.

To get AHC back to 100% you'll need to replace globes and then inspect neutral pressures. That will tell you how you need to adjust torsion bars (completely free) and which rear springs are needed (either new AHC springs or King Springs at $200-300).

AHC gets a bad rap from exactly this situation and people get scared into replacing it with a "simple" suspension system that average joe mechanic can better understand and troubleshoot.

My advice is to seriously consider your complete options before tearing anything out. Often times, the cheap and best performing solution is fixing/maintaining AHC.

 

[suprarx7nut]

he mentions and showed me spots where it was leaking minorly at 2 points, a reason why the graduations were becoming lower within the past few months.

My impression based on your posts so far is that this mechanic is not familiar with AHC or he wasn't able to properly translate his findings to you. I think you need to find another mechanic more versed in this system (unfortunately, not an easy task), or you should learn yourself and do your own diagnostics. Techstream can be had pretty cheap these days.

 

[marcuslx470]

My impression based on your posts so far is that this mechanic is not familiar with AHC or he wasn't able to properly translate his findings to you. I think you need to find another mechanic more versed in this system (unfortunately, not an easy task), or you should learn yourself and do your own diagnostics. Techstream can be had pretty cheap these days.

I appreciate the help very. I think I will try and look forward to trying to maintain it then if it is a simple fix here and there. it definitely is scary and intimidating when something so serious like that comes to play and I just don't want it to end up failing on me when I'm out camping or on road trips 1,000+ miles from home.

ill take a look at it over again and see if i cant get someone who is well experienced with the AHC system. cheers!

 

[Mbchance]

he mentions and showed me spots where it was leaking minorly at 2 points, a reason why the graduations were becoming lower within the past few months.

See if you the shocks are leaking. If that is the cause of your leak then getting the pressures under control might fix that problem. If not, you can rebuild the shock or buy a new one.

 

[marcuslx470]

@suprarx7nut if you don’t mind, can i send you pictures of what it looks like underneath of what he was talking about and you can point me in the right direction of where i can start?

 

[suprarx7nut]

@suprarx7nut if you don’t mind, can i send you pictures of what it looks like underneath of what he was talking about and you can point me in the right direction of where i can start?

By all means, go ahead. Post them up here so other can chime in as well. I'm no master mechanic, just an enthusiast with an enormous amount of time at a PC (thanks day job) and a lot of wrench time. Other folks will add helpful info too!

 

[marcuslx470]

By all means, go ahead. Post them up here so other can chime in as well. I'm no master mechanic, just an enthusiast with an enormous amount of time at a PC (thanks day job) and a lot of wrench time. Other folks will add helpful info too!

first picture is front driver side, as you can see the boot is a bit torn
2nd pictures is passenger side boot, not as bad as the drivers side
3rd pic is the AHC reservoir and i used my knife to show exactly where the level stands in neutral position cause it is kind of bright and hard to see
4th picture is the driver side little chamber and i checked the bleeders and everything else i don’t see any signs of sweating or leaking, but that’s mostly all he pointed out. thoughts ?

edit: i can take a look around now and again in the next few days and see if i actually see any signs of leaking as he said

 

[Stevehats]

I think you can replace the suspension for about the same price you will have to replace the bulb

If you are low on gradations, that means your globes (pressurized nitrogen balls) are worn out and need replacement. A full set is around $1000 and is basically the only expected wear item in the system. A full set of these is far cheaper than a comparable traditional shock set.

I don't know what the rear main seal is in this context. The "rear main seal" is the crankshaft seal between the engine and transmission. If he means something related to AHC, it probably just needs a new gasket or o-ring. It may be leaking because the system hasn't be adjusted to your added weight and is pressurizing more than normal to attempt to keep your rig at the desired height.

The expensive parts of AHC that have any likelihood of failure are the pump and globes. Your globes are worn and need replacement ( so it seems), but replacing all of them is cheaper than a traditional suspension swap with new, good parts.

To get AHC back to 100% you'll need to replace globes and then inspect neutral pressures. That will tell you how you need to adjust torsion bars (completely free) and which rear springs are needed (either new AHC springs or King Springs at $200-300).

AHC gets a bad rap from exactly this situation and people get scared into replacing it with a "simple" suspension system that average joe mechanic can better understand and troubleshoot.

My advice is to seriously consider your complete options before tearing anything out. Often times, the cheap and best performing solution is fixing/maintaining AHC.

I have recently been thinking about replacing the AHC because I thought my shocks may be going bad. In the end, I have decided to keep the system if I can diagnose my problem. With that being sade I think you can replace the whole suspension for the price fo new globes. I was looking at a Dobinson set up for right around 1000. I understand the thought process though on wanting to go standard with a heavy set up. You will where out those bulbs quicker with heaver set up. I think in the long run a traditional setup would be cheaper to maintain. I would love to hear others with more experience on this because that is just my guess. Like I said I am keeping mine but this was my thought process on fixing vs replacing. I do agree that the system needs to be better diagnosed before you go that route.

 

[suprarx7nut]

first picture is front driver side, as you can see the boot is a bit torn
2nd pictures is passenger side boot, not as bad as the drivers side
3rd pic is the AHC reservoir and i used my knife to show exactly where the level stands in neutral position cause it is kind of bright and hard to see
4th picture is the driver side little chamber and i checked the bleeders and everything else i don’t see any signs of sweating or leaking, but that’s mostly all he pointed out. thoughts ?

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edit: i can take a look around now and again in the next few days and see if i actually see any signs of leaking as he said

1. Ball joints. Looks like you could use at least one new boot. That's a cheap fix and not terribly hard. Not fun, but not a full weekend affair.
2. You need more AHC fluid. You're low and I don't think you can do the gradation test when you're that low on fluid.
3. That looks like a normal accumulator. No problem there. no idea what he was talking about.

 

[marcuslx470]

1. Ball joints. Looks like you could use at least one new boot. That's a cheap fix and not terribly hard. Not fun, but not a full weekend affair.
2. You need more AHC fluid. You're low and I don't think you can do the gradation test when you're that low on fluid.
3. That looks like a normal accumulator. No problem there. no idea what he was talking about.

1) i don’t mind, i usually like working on my LX and the overall learning experience. do you recommend any threads on “how to’s” on how to go about replacing ? and what about parts i can get that are closest to the OEM for a good cost? also if i’m going to take a part some things, would it be also to might as well replace some other things while i’m inside and under the truck? maybe some insurance ?
2) cant i just top it off ? or would i have to flush and bleed the entire system? i’ve seen a couple write ups and videos so i’m sorta kinda familiar with it, just wanna make sure the pressures are ok.

 

[suprarx7nut]

1) i don’t mind, i usually like working on my LX and the overall learning experience. do you recommend any threads on “how to’s” on how to go about replacing ? and what about parts i can get that are closest to the OEM for a good cost? also if i’m going to take a part some things, would it be also to might as well replace some other things while i’m inside and under the truck? maybe some insurance ?
2) cant i just top it off ? or would i have to flush and bleed the entire system? i’ve seen a couple write ups and videos so i’m sorta kinda familiar with it, just wanna make sure the pressures are ok.

1. I haven't replaced the ball joint boots alone, so I'll have to let others chime in. Personally, I'd buy only OEM boots. That's a cheap enough part that the cost savings isn't worth any reduced product quality or fitment risks.
2. Just top it off. After cycling the system once, put it in N. Fill the reservoir to the min line. Now repeat the gradation test on a level surface.

3. (optional, but recommended) go buy yourself a techstream cable on Amazon and test pressures. I bet you have some adjusting to do.

 

[marcuslx470]

1. I haven't replaced the ball joint boots alone, so I'll have to let others chime in. Personally, I'd buy only OEM boots. That's a cheap enough part that the cost savings isn't worth any reduced product quality or fitment risks.
2. Just top it off. After cycling the system once, put it in N. Fill the reservoir to the min line. Now repeat the gradation test on a level surface.

3. (optional, but recommended) go buy yourself a techstream cable on Amazon and test pressures. I bet you have some adjusting to do.

ill most likely do that 3rd option! i got some learning to do now again thank you for the help and i’ll see what i can do !

 

[gregnash]

So after reading this, this seems to be a bit of a predatory tactic that the service guy is looking to either get you to spend money with them replacing the system or replacing the vehicle all together with a new one.

There are a few AHC threads that will help you out with how to go through the system yourself. If you have a windows laptop look up the "How to Techstream in 5 minutes" thread and start there. Like @suprarx7nut is saying, there is lots you can do on your own to get this system up to snuff, doesn't look like anything is nasty, leaky or whatever enough to necessitate replacement asap.

Also, UCA ball joints can be pressed out. You can purchase a whole kit (upper and lower ball joints) from Cruiser Outfitters for about $200 (i think) and be done with it. Will be some time wrenching in your garage but you will get familiarized with the front suspension some. I am in the same boat as you and need to replace mine.

 

[marcuslx470]

So after reading this, this seems to be a bit of a predatory tactic that the service guy is looking to either get you to spend money with them replacing the system or replacing the vehicle all together with a new one.

There are a few AHC threads that will help you out with how to go through the system yourself. If you have a windows laptop look up the "How to Techstream in 5 minutes" thread and start there. Like @suprarx7nut is saying, there is lots you can do on your own to get this system up to snuff, doesn't look like anything is nasty, leaky or whatever enough to necessitate replacement asap.

oh i did hear about the tech stream, i’ll do my digging and see how can i use it. but i did read that it’s for windows as you said. what if i own all apple products ? would i still be able to access it ?