Me and my pal AHC, before I buy an LX470

[Fireguy615]

First the backstory.....100-series noob about to pull the trigger on a year 2000 2-owner mall-rated LX470 with 182,000 miles. Its about 1,000 miles away, fly-out-drive-back scenario, but its a clean, bone-stock, western no-rust 470 for $7K. It has no issues as it sits except a broken antenna, and I will have to give it its second timing belt as my first incurred cost.

Now the question....This forum is littered with threads and topics from people who have had problems with their AHC system in their 470s...stuck up, stuck down, going up and down on its own, riding like crap, etc etc. Repair costs on this system are not wallet-friendly, usually averaging about $1K per wheel to fix from a stealership, or about $2K to rip it all off and replace with an LC setup. One guy stated " You are are only 1 of 2 people...those who have had AHC problems, and those who will". So should the "potential" of AHC headaches completely shy me away from buying a 470 and steer towards an LC, or should I stop being a wuss and just roll out and grab a nicely-priced 470 and not worry about it??

 

[Tredwards]

Just bought a 2005 LX470. Has AHC. no issue so far. However this is not to say problems won't occur in the future. I had @beno inspect vehicle for me prior to purchase. We had a discussion about AHC in LX vs the traditional setup in a LC. His thought at the time was if the AHC works why get rid of it, if there is a problem then you can consider your options. I am mechanically inclined and can remove in future if having a problem, however currently I have no issues and it works well and has a fantastic ride. My plan is to remove if expensive costs occur and if it remains stable i'll run it. Just my .02 cents

 

[SWUtah]

If you have a problem drive it up to Slee Off-road in Golden Co. Have him install OME 2" lift and a set of step sliders. Give him a call he will price everything out for you. Plus he can do your timing belt and water pump. Then you will know everything was done by the best.

 

[trizzo]

AHC is great, sooooo smooth. my wife and kids love riding in my LX. sure, there can be problems with it, but its fairly easy to troubleshoot. even replacing globes is cheaper than you'd think if you buy from an international source (amayama). a few quick tests and checks will tell you if you are in for problems soon or if things are good to go. @PADDO is literally Dr AHC and has posted tons of data.

 

[Phat1842Many]

Pick up that truck. When the AHC dies swap it out. You can try to trouble shoot it but you risk putting good money (and time) after bad.

I just swapped mine out and while I liked the functionality of the system, I'm happy to trade that off for the reliability of simplicity.

Phat-

 

[jhanley]

Seems like every 20 posts an AHC thread pops-up. It's getting redundant, but here's my take:

1 - AHC is awesome.

2 - If you buy a Landcruiser (not an LX), the 15 year old suspension is tired and in need of replacement anyways.

3 - Do NOT judge AHC failures based on problem-threads on a forum. For every IH8MUD thread complaining of failures, there are thousands of trucks running without problem. Failures are uncommon.

4 - AHC is awesome.

 

[TomEf]

I like my AHC. A while back I had it dropping into limp mode while on a rocky access trail, but then I changed the fluid and noticed that it had been a little low. No problems since then, and I don't think my LX (2001) had been very lovingly maintained after the original owner.

 

[Mitya]

I had a lot of issues with AHC (got 98 LX), but its the best type of suspension that i tryed so far and even though it was pricy and i thought a couple of times to !@#% it and go to standart 100 or OME, but now i got AHC working nice and its superb. Best advice i could give: inspect AHC before buy (Shocks, accumulators, main accumulator, tubes (!!!), pump (look for some loud noise, which will tell you that its going to die soon) etc), so you could lower the price.

 

[jhanley]

Also, If AHC goes dead on you, or isn't worth repairing, you can go back to stock for much less than purchasing an OME suspension. Test the system and like @Mitya said - check all associated parts.

 

[jLB]

Also, If AHC goes dead on you, or isn't worth repairing, you can go back to stock for much less than purchasing an OME suspension.

I assume you're talking about the "non-AHC" OEM components for a Land Cruiser. The ride might be more appropriate with OEM vs OME on a otherwise stock vehicle, but cheaper?

I thought I remembered new OEM torsion bars retailing for ~$450 each, and new rear coils for ~$200 each. I know the shocks are relatively cheap and retail around $50 each. 900+400+200=1500 and I know I've seen the OME kit for just under $1000 (more like $1500 if you want to add a diff drop and UCAs).

 

[n55luvr]

FWIW, I was just pricing out OEM suspension parts. Cheapest OEM tbars are $300 each (not sure of shipping). Cheapest springs I found were $310 delivered to my door (just received them). I bought OEM shocks last year for around $35 a corner if I recall. So I think you can get all those OEM parts for around $1100 or so.

 

[Ramathorn15]

Fellow ABQian here. I just picked up an 06' LX470 and the AHC is great. I would say go for it. From what I can tell, most people have issues when the system is tainted by an unknowing technician at jiffylube who puts washer/brake fluid in the AHC reservoir. Otherwise, they seem pretty reliable. A plus of the LX is that you get the AHC. If it goes bad, you have three options of repairing it, replacing it with a OME lift, or stock LC suspension. with the LC, you only have two of those options (repair stock, or lift). Also, if you can do your own work, the repairs on the AHC are not nearly as expensive as the dealer says. I believe you can get all 4 actuators for around 800 online and install them yourself.

With the AHC in working condition, you can do the simple modification to trick the system into being in the H position when it thinks its in the N position. this is pretty much a free lift, minus the diff drop.

 

[PabloCruise]

@PADDO is literally Dr AHC and has posted tons of data.

His posts are great! We got a '99 w/ AHC and the loves it. It is her DD, and she is short (5'02"), so a lift would be a real drag for her. N height AHC + 285s are about as tall as we could go for her, so I like the idea of the AHC.

It sounds like if you change out the fluid regularly, and check the system pressures, these systems can last for quite a while.

 

[jhanley]

I assume you're talking about the "non-AHC" OEM components for a Land Cruiser. The ride might be more appropriate with OEM vs OME on a otherwise stock vehicle, but cheaper?

I thought I remembered new OEM torsion bars retailing for ~$450 each, and new rear coils for ~$200 each. I know the shocks are relatively cheap and retail around $50 each. 900+400+200=1500 and I know I've seen the OME kit for just under $1000 (more like $1500 if you want to add a diff drop and UCAs).

Sorry, I should have been more specific. I wouldn't source new parts, as members continually post suspension parts for sale once they've upgraded.

Might take longer, but if you're not looking for lift, is the way to go.

 

[TeCKis300]

With the AHC in working condition, you can do the simple modification to trick the system into being in the H position when it thinks its in the N position. this is pretty much a free lift, minus the diff drop.

I likewise really enjoy the AHC system. Since we're talking about keeping the system maintained and keeping it reliable...

I would not advise the above mod, in that manner, as it specifically is one of the ways to premature wear and failure. Consider that in a normal AHC system, approximately half of the vehicles weight is acting on AHC and half on the mechanical spring. Forcing the system into H all the time is proportionately putting the majority of the load on AHC and little on the mechanical spring. This adds wear and tear to the AHC system, and minimizes your [constant height] load carrying abilities.

The proper way to lift with AHC, is to adjust the position of the height sensor. Then with a scan tool, adjust the front torsion bar, and change springs/add spacers in the rear, until neutral pressures are at OE spec. This makes sure that the mechanical springs are bearing their share of the load. Also note that you don't want to lift too far with AHC, if you want to make use of the 'H' position, as the suspension will run out of stroke in that setting.

 

[Ramathorn15]

I likewise really enjoy the AHC system. Since we're talking about keeping the system maintained and keeping it reliable...

I would not advise the above mod, in that manner, as it specifically is one of the ways to premature wear and failure. Consider that in a normal AHC system, approximately half of the vehicles weight is acting on AHC and half on the mechanical spring. Forcing the system into H all the time is proportionately putting the majority of the load on AHC and little on the mechanical spring. This adds wear and tear to the AHC system, and minimizes your [constant height] load carrying abilities.

The proper way to lift with AHC, is to adjust the position of the height sensor. Then with a scan tool, adjust the front torsion bar, and change springs/add spacers in the rear, until neutral pressures are at OE spec. This makes sure that the mechanical springs are bearing their share of the load. Also note that you don't want to lift too far with AHC, if you want to make use of the 'H' position, as the suspension will run out of stroke in that setting.

I completely agree. What I was referring to by tricking the system is the adjustment of the height sensors. Not the Slee always in H mod. Thanks for pointing out the correction on the torsion bars and spacers.

 

[PADDO]

I likewise really enjoy the AHC system. Since we're talking about keeping the system maintained and keeping it reliable...

I would not advise the above mod, in that manner, as it specifically is one of the ways to premature wear and failure. Consider that in a normal AHC system, approximately half of the vehicles weight is acting on AHC and half on the mechanical spring. Forcing the system into H all the time is proportionately putting the majority of the load on AHC and little on the mechanical spring. This adds wear and tear to the AHC system, and minimizes your [constant height] load carrying abilities.

The proper way to lift with AHC, is to adjust the position of the height sensor. Then with a scan tool, adjust the front torsion bar, and change springs/add spacers in the rear, until neutral pressures are at OE spec. This makes sure that the mechanical springs are bearing their share of the load. Also note that you don't want to lift too far with AHC, if you want to make use of the 'H' position, as the suspension will run out of stroke in that setting.

and the only other things I'd add are when you override the height control system to stay in H your systems' pressures are approximately 2-2.5MPa above Normal height pressure. This higher pressure impedes the adaptive variable suspensions' ability to function properly (poor damping overall) and this is further exacerbated by accumulator globes that have aged and don't have their "new in box" full pressure charges.

 

[Ramathorn15]

and the only other things I'd add are when you override the height control system to stay in H your systems' pressures are approximately 2-2.5MPa above Normal height pressure. This higher pressure impedes the adaptive variable suspensions' ability to function properly (poor damping overall) and this is further exacerbated by accumulator globes that have aged and don't have their "new in box" full pressure charges.

This pressure can be counteracted by adjusting the torsion bars and adding coil spacers in the rear, right?

 

[PADDO]

This pressure can be counteracted by adjusting the torsion bars and adding coil spacers in the rear, right?

Absolutely manageable for the most part. It gets a bit tricky though when you have additional weight and additional height and degraded damper globes and 10 ply tires and squished, hardened bushings and cushions throughout

 

[OG 91 LC]

Stop being such a wuss and roll out!!!!!

May sure the system is working properly and pull the trigger.

If it craps out, then fix it or ditch it and go standard or lift.

That being said make sure not to neglect other components of the truck that could also be potential issues, like TB and steering rack, to name a few.

I drive my LX once a week. I drove it to work today. It feels like I'm on a cloud while driving. AHC is RAD!!!!!