AHC - fix or replace? (2 Viewers)

[dallasag]

I have an 07 LC with 160k miles and AHC, mostly highway cruiser. My rear AHC pressures are reading 7.8. I am getting 9 ticks on the graduation test.

I estimate that new rear springs + spacers + install will be slightly less than $800. So the question is, should I spend the money to bring the rear pressure down, or bite the bullet and yank the whole system for traditional springs/shocks to for a total cost of ~$2k?

 

[TXLX100]

I have an 07 LC with 160k miles and AHC, mostly highway cruiser. My rear AHC pressures are reading 7.8. I am getting 9 ticks on the graduation test.

I estimate that new rear springs + spacers + install will be slightly less than $800. So the question is, should I spend the money to bring the rear pressure down, or bite the bullet and yank the whole system for traditional springs/shocks to for a total cost of ~$2k?

If it still rides good, I'd replace the rear springs, adjust the T-bars and keep going. My 1998 needed new accumulators and I was very hesitant to buy aftermarket ones and definitely didn't want to spend $2k on new Toyota parts. Currently doing the OME conversion, the kit was about $1k, and I picked up a slee diff drop for $200.

 

[tacoduck]

swap the fluid and see if that helps. Im constantly amazed at how good the AHC system is under normal operating conditions. Id spend 1 hour and 40$ in fluid and then reassess.

 

[68W65D]

If it still rides good, I'd replace the rear springs, adjust the T-bars and keep going. My 1998 needed new accumulators and I was very hesitant to buy aftermarket ones and definitely didn't want to spend $2k on new Toyota parts. Currently doing the OME conversion, the kit was about $1k, and I picked up a slee diff drop for $200.

You can usually get a full set of OEM accumulators for around $1,200

 

[TXLX100]

You can usually get a full set of OEM accumulators for around $1,200

Nice. I really like that system, sad to see it go. But the loads I'm going to use are much heavier and going to be using it off highway more and think replacing it is the best option for me.

 

[Snowrydr01]

When i bought my lx the numbers were low and i am still debating on fixing or using standard springs. My middle ground was to install airbags to handle the rear. It was only $150, only took a few hours, got my numbers perfect with almost no load for normal use, and then when we REALLY load it up for family road trips i put a little more air in and my numbers are good and its comfortable for the drive.

I will point out that there wasnt enough hose to run two independent lines to where i wanted to point them so i needed a second hose kit but it couldve been a 4-5 hour relaxed pace job if i had everything at once.

 

[Julian Stead]

Why not just spacers, why both? And a fluid flush if required. Or are you looking for a excuse to dump it.

 

[BEG]

Nice. I really like that system, sad to see it go. But the loads I'm going to use are much heavier and going to be using it off highway more and think replacing it is the best option for me.

Replace the sagging factory springs with King AHC springs. Add bags, if you need them. The AHC really is great off-road and the solutions to its weaknesses are often cheaper than replacing the whole thing.

 

[geanes]

I'm on the fence with this one as well. Once any major element of my AHC goes, I'm thinking a swap to ToughDog or IronMan foam makes perfect sense. However, one of the GREATEST things about AHC is it's adjustability: I can raise up for a little more body clearance off-road and, more importantly, lower it all the way down to actually get in my garage. Without it, my rig would be outdoors 24/7....in Texas

Losing that functionality would be a major issue. Currently evaluating putting in King Springs and airbags in preparation for the rear bumper and anticipated drawer system (target February/March). Hopefully that can handle the added weight.

 

[bozncsurf]

If it still rides good, I'd replace the rear springs, adjust the T-bars and keep going. My 1998 needed new accumulators and I was very hesitant to buy aftermarket ones and definitely didn't want to spend $2k on new Toyota parts. Currently doing the OME conversion, the kit was about $1k, and I picked up a slee diff drop for $200.

where did you get a slee diff drop for $200 ? I want one.

 

[BEG]

I think people give up too easily on AHC, either because they think it's too expensive to fix or they've heard it's not robust enough off-road. I don't think either is true.

A set of custom-pressurized, remote-reservoir, rechargeable AHC globes (shocks) that can be adjusted from within the cab at the turn of a dial are about $200 shipped per corner.
A set of ICON CDCV custom-tuned, remote-reservoir, adjustable shocks are $650 per corner and there's no in-cab adjustment control.

A set of conventional OME 2865 springs are about $170 a pair.
A set of AHC-specific King KTRS79 springs are about $145 a pair.

A set of OME 303001 non-AHC torsion bars is about $300 a pair.
An upgraded set of t-bars for an AHC rig is as cheap as finding a set of LC take-offs from someone who upgraded.

Even if the prices were equal or greater for AHC (if you have extreme neglect and/or failure of a major component), you still give up the ability to raise and lower the suspension for clearance off-road, better MPGs on road, lower wear on suspension components, ability to fit in garages/ under off-road obstacles, etc. That's a big step backwards, IMO.

 

[geanes]

I think people give up too easily on AHC, either because they think it's too expensive to fix or they've heard it's not robust enough off-road. I don't think either is true.

A set of custom-pressurized, remote-reservoir, rechargeable AHC globes (shocks) that can be adjusted from within the cab at the turn of a dial are about $200 shipped per corner.
A set of ICON CDCV custom-tuned, remote-reservoir, adjustable shocks are $650 per corner and there's no in-cab adjustment control.

A set of conventional OME 2865 springs are about $170 a pair.
A set of AHC-specific King KTRS79 springs are about $145 a pair.

A set of OME 303001 non-AHC torsion bars is about $300 a pair.
An upgraded set of t-bars for an AHC rig is as cheap as finding a set of LC take-offs from someone who upgraded.

Even if the prices were equal or greater for AHC (if you have extreme neglect and/or failure of a major component), you still give up the ability to raise and lower the suspension for clearance off-road, better MPGs on road, lower wear on suspension components, ability to fit in garages/ under off-road obstacles, etc. That's a big step backwards, IMO.

I've always wondered if I could just transplant the LC torsion bars into an LX without fudging up the AHC. I have an IronMan bullbar currently and have a Smittybilt 10k X20 winch (synthetic line) inbound and ordering the Slee skid plates. I figured my LX tbs wouldn't handle that added weight well at all. I had to add 2.25 rotations when I added the bullbar to get back into balance.

As for off-road prowess: mine handled the San Juans, Big Bend, Webster and Mosquito passes with ease.

Attached is my LX meeting an LC at the top of Mosquito. I'm on 275/70/18 KO2. The LC was on 35" with an IronMan lift. I went everywhere he did with comfort

 

[TXLX100]

where did you get a slee diff drop for $200 ? I want one.

A friend had one laying around

 

[TXLX100]

I've always wondered if I could just transplant the LC torsion bars into an LX without fudging up the AHC. I have an IronMan bullbar currently and have a Smittybilt 10k X20 winch (synthetic line) inbound and ordering the Slee skid plates. I figured my LX tbs wouldn't handle that added weight well at all. I had to add 2.25 rotations when I added the bullbar to get back into balance.

As for off-road prowess: mine handled the San Juans, Big Bend, Webster and Mosquito passes with ease.

Attached is my LX meeting an LC at the top of Mosquito. I'm on 275/70/18 KO2. The LC was on 35" with an IronMan lift. I went everywhere he did with comfort

View attachment 1589771

I'm sure you could. Not being "search guy" but I bet someone here has done it. It would be comparable to adding a stronger spring in the rear or using air bag to offset some weight.

 

[dallasag]

I very much appreciate folks taking the time to comment. I forgot to add - I changed the AHC fluid 5 years ago at 120k and changing now appears premature. I blindly cranked torsion bars about a year ago and my recent front pressure reading was within spec.

I use the LC for work and highway travel, and I am not interested in a lift. I also don't tow or carry unusually heavy loads.

I am definitely not itching for an excuse to ditch the system. Based upon the comments, I am leaning towards replacing the springs and adding spacers, and hoping I can get another 50k miles out of the AHC system without major costs. The reason I would do springs and spacers is I read the other posts and it doesn't seem that one or the other by itself will be enough to drop the pressure by 1.

 

[dallasag]

Also does anyone have a link to the AHC King springs from a US seller? Thanks!

 

[PabloCruise]

I very much appreciate folks taking the time to comment. I forgot to add - I changed the AHC fluid 5 years ago at 120k and changing now appears premature. I blindly cranked torsion bars about a year ago and my recent front pressure reading was within spec.

I use the LC for work and highway travel, and I am not interested in a lift. I also don't tow or carry unusually heavy loads.

I am definitely not itching for an excuse to ditch the system. Based upon the comments, I am leaning towards replacing the springs and adding spacers, and hoping I can get another 50k miles out of the AHC system without major costs. The reason I would do springs and spacers is I read the other posts and it doesn't seem that one or the other by itself will be enough to drop the pressure by 1.

5 years does not seem premature relative to the cost of the system components.
King Springs can drop the pressure down a good bit by themselves. Try spacers, or springs and re-check pressure.

 

[BEG]

The reason I would do springs and spacers is I read the other posts and it doesn't seem that one or the other by itself will be enough to drop the pressure by 1.

King springs alone can easily drop your pressures by 4mpa, depending on where they are now.
King Springs AHC KTRS-79

 

[RunTheDistance]

I think people give up too easily on AHC, either because they think it's too expensive to fix or they've heard it's not robust enough off-road. I don't think either is true.

A set of custom-pressurized, remote-reservoir, rechargeable AHC globes (shocks) that can be adjusted from within the cab at the turn of a dial are about $200 shipped per corner.
A set of ICON CDCV custom-tuned, remote-reservoir, adjustable shocks are $650 per corner and there's no in-cab adjustment control.

A set of conventional OME 2865 springs are about $170 a pair.
A set of AHC-specific King KTRS79 springs are about $145 a pair.

A set of OME 303001 non-AHC torsion bars is about $300 a pair.
An upgraded set of t-bars for an AHC rig is as cheap as finding a set of LC take-offs from someone who upgraded.

Even if the prices were equal or greater for AHC (if you have extreme neglect and/or failure of a major component), you still give up the ability to raise and lower the suspension for clearance off-road, better MPGs on road, lower wear on suspension components, ability to fit in garages/ under off-road obstacles, etc. That's a big step backwards, IMO.

Thanks for posting this. I am starting a hunt for a 100 series and was considering eliminating AHC equipped versions but this makes it sound doable.

 

[ChuckB]

My latest pressure in the rear was 7.7mpa. I’m in the process of ordering new AHC springs and spacers as im not ready to ditch the system yet. It’s been reported that 30mm spacers will drop the pressure by 0.6mpa. Mine won’t be installed until after the holidays.