How much weight to add-on for an AHC?

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

stridertexas

stridertexas

10 Year
Joined
Apr 29, 2013
Threads
52
Messages
547
I know this thread might seem odd, but I'm torn on how much weight I can add to my LC with keeping the AHC system running well for as long as possible. I've read til my eyes have crossed.

Right now my '07 LC AHC is bone stock with 101k. I like the AHC and want to keep it functional for as long as possible, but would like to start adding some goodies to have fun with on the weekends when my son and I go out mtn biking and trail riding. I have a rear KUAT dual bike carrier now that we use to take the bikes to local parks here in TX.

Would adding a TJM bumper and a Gamiviti roof rack be too much weight to severely impact the longevity of the AHC? Christo at Slee says the AHC can handle an additional 800lbs of weight and by adding a bumper and rack I'm at about 400lbs of that limit. I might remove the running boards and sliders once the kids get a little older.

So would adding those items really shorten the life span of my AHC? Is the 800lbs including driver and passengers?
 
Load capacity for the LX 470 is roughly 1000lbs, with some margin above that. The 800lbs Christo mentions most likely is after adding the driver.

I finally built a spreadsheet to see how close I was approaching the limit when I loaded up for a trip. It's worth the effort. The big hit comes if you pull a trailer with 200-400lbs of hitch weight or adding passengers.

I'd just make a list and start weighing stuff like your going backpacking with a big pack and you'll be surprised how fast things add up. This time around on my LX 570, I really look at every pound.

It's why most folks that know they are going heavy opt for a LC with aftermarket suspension or replace the AHC. Just ease your way into it and you'll see how well it does work, within its limits.
 
stridertexas said:
I know this thread might seem odd, but I'm torn on how much weight I can add to my LC with keeping the AHC system running well for as long as possible. I've read til my eyes have crossed.

Right now my '07 LC AHC is bone stock with 101k. I like the AHC and want to keep it functional for as long as possible, but would like to start adding some goodies to have fun with on the weekends when my son and I go out mtn biking and trail riding. I have a rear KUAT dual bike carrier now that we use to take the bikes to local parks here in TX.

Would adding a TJM bumper and a Gamiviti roof rack be too much weight to severely impact the longevity of the AHC? Christo at Slee says the AHC can handle an additional 800lbs of weight and by adding a bumper and rack I'm at about 400lbs of that limit. I might remove the running boards and sliders once the kids get a little older.

So would adding those items really shorten the life span of my AHC? Is the 800lbs including driver and passengers?
Click to expand...
I'm contemplating doing the same, the suspension system i want is 3600 from just differentials with icons.... so that's a hefty spot but i'd like to see how much i could push the current ahc system without changing the suspension immediately as well
 
What would be nice is to have someone do a partial or full 'armored' up Bilstein suspension on a US LX. Kinda hoping Christo would see what might be possible/cost effective with his 'new' LX 570 to increase the 200 series' AHC capacity vs just replacing it with a traditional suspension.

The Bilstein B6 package seems to be the common solution, though I was hoping that just integrating higher capacity shocks w/o the other components, etc., would buy us some additional capacity while maintaining the AHC variable dampening and height features.

Given the greater number of somewhat affordable LX's vs LCs 200s coming on the market after eight years, I assume he's at least considered it.

Bilstein Products | ACE Armour

Thinking along the lines of what this owner was able to source:
Transafrica with a Land Cruiser 200 (Diesel)
 
AHC can be augmented for heavy weight. Just like how a standard suspensioned Hundy needs to be upgraded.

There are upgraded AHC heavy springs and torsion bars available. Others have used 80-series springs.
 
cainventure said:
I'm contemplating doing the same, the suspension system i want is 3600 from just differentials with icons.... so that's a hefty spot but i'd like to see how much i could push the current ahc system without changing the suspension immediately as well
Click to expand...

Agreed. Spacing these costs out would sure help...
 
Txt-tortoise I couldn't agree more.

The level of suspension I'm comfortable paying for (eventually), I would hope I could keep the functionality of the AHC, since I personally rather enjoy it's purpose.
 
I'm still running the AHC with T bars cranked up a little and 30mm rear spacers. Curb weight on a 2006 is listed at 5425 lbs. I grossed 6560 driver, full tank,with sliders,skid plates,rear drawers, and a rear bumper with a jack. I have been running this set up for about 10k now and it does ok on the pavement. It is not enough for off road travel, and I will probably try new replacement rear coils with the spacers or 80 series coils. There's lots to like about AHC, but I think modifying it is a temporary solution to a constant problem...
 
@wtmtnterror what are your neutral pressures? Usually adding 30mm spacers just gets stock weight vehicle's rear neutral pressure back in range. Not really enough to adequately compensate for all that extra permanent weight.
 
TeCKis300 said:
AHC can be augmented for heavy weight. Just like how a standard suspensioned Hundy needs to be upgraded.

There are upgraded AHC heavy springs and torsion bars available. Others have used 80-series springs.
Click to expand...

Do you have a link or info on the upgraded rear springs designed for the AHC system? My google results are lacking. I am adding a roof rack, drawer system and rear bumper soon and need to figure out the rear springs for all of this extra weight while still maintaining the AHC functionality.
 
i love that this thread is staying alive. The more info the better for us AHC guys : )
 
ihadmail said:
Do you have a link or info on the upgraded rear springs designed for the AHC system? My google results are lacking. I am adding a roof rack, drawer system and rear bumper soon and need to figure out the rear springs for all of this extra weight while still maintaining the AHC functionality.
Click to expand...
Have a look at King Springs KTRS-79s
 
FWIW changing the suspension doesn't really increase your load capacity or towing capacity. There's a lot more involved with those calculations than just springs and shocks.
 
stridertexas said:
...how much weight I can add to my LC with keeping the AHC system running well for as long as possible. I've read til my eyes have crossed....
Right now my '07 LC AHC is bone stock with 101k. I like the AHC and want to keep it functional for as long as possible, but would like to start adding some goodies to have fun with on the weekends when my son and I go out mtn biking and trail riding....
So would adding those items really shorten the life span of my AHC? Is the 800lbs including driver and passengers?
Click to expand...
It's not about how much weight you add, but what AHC Neutral Pressures you run. If you add weight, you also have to increase the capacity of the steel springs so that your gas springs (aka spheres or accumulators) carry only as much as they are designed for. So, fire up your TechStream, check pressures, and adjust/change torsion bars and coils according to how much weight you add. For the ahc, it doesn't matter if you add 2000 lb as long as you also change the springs accordingly. (Although, at that weight the damping would start to suffer)

For the damping effect (shock absorber function) of the ahc, it is crucial that the Neutral Pressure is within the specified range. If you put in too stiff coils so that the ahc pressure is close to zero, it would be like driving without shocks.

For ahc longevity, you could argue that if you always leave it in LO when parked, the accumulators would last longer, and the coils shorter. And if you always park it in HI, the accumulators would carry most of the weight and live shorter, while the coils could live longer.
 
uHu said:
It's not about how much weight you add, but what AHC Neutral Pressures you run. If you add weight, you also have to increase the capacity of the steel springs so that your gas springs (aka spheres or accumulators) carry only as much as they are designed for. So, fire up your TechStream, check pressures, and adjust/change torsion bars and coils according to how much weight you add. For the ahc, it doesn't matter if you add 2000 lb as long as you also change the springs accordingly. (Although, at that weight the damping would start to suffer)

For the damping effect (shock absorber function) of the ahc, it is crucial that the Neutral Pressure is within the specified range. If you put in too stiff coils so that the ahc pressure is close to zero, it would be like driving without shocks.

For ahc longevity, you could argue that if you always leave it in LO when parked, the accumulators would last longer, and the coils shorter. And if you always park it in HI, the accumulators would carry most of the weight and live shorter, while the coils could live longer.
Click to expand...


I appreciate you spelling this out. It seems quite simple... Guess I'm on the hunt for what spring types are appropriate for adding about 500lbs of weight to my AHC.

The TJM bumper I'm told is 245lbs. The rack is about 50-75lbs, and slider steps I believe are adding about another 100-200lbs.
 
Simplespirit said:
FWIW changing the suspension doesn't really increase your load capacity or towing capacity. There's a lot more involved with those calculations than just springs and shocks.
Click to expand...

In principle, I definitely agree with you.

Though that doesn't stop the rest of us from trying. It's well known the Land Cruiser series is overbuilt, largely for durability. The way I interpret that is that its components have additional strength beyond its stated capacities, such that it can withstand and be reliable for long term use (or shorter term abuse).

Another way I look at it is that the LC is a heavy duty platform. It's stated carrying capacities are largely due to its soft spring rates for the purpose of off road ability and flex. Unlike most trucks in the states, which are built with high spring rates for load carrying capacity. By augmented the stock suspension, we should be able to easily gain some additional capacities. Because in reality, that's what the manufacturers are largely doing. Though of course validated for longer term durability at those higher capacities. Which we know the LC will already has baked in.

And we know Toyota does it for the LC in other markets with stronger springs alone.
 
Lifted AHC I run anywhere from no weight to ~2000lbs towing and everything in between. Do it all with air bags some tuning of the AHC and it passes on wife approved.

In the past I tried it without air bags and the AHC would kicked in low for exceeded the AHC capabilities and the ride was bouncy.
 
LandCruiserPhil said:
Lifted AHC I run anywhere from no weight to ~2000lbs towing and everything in between. Do it all with air bags some tuning of the AHC and it passes on wife approved.

In the past I tried it without air bags and the AHC would kicked in low for exceeded the AHC capabilities and the ride was bouncy.
Click to expand...


This is what I'm looking for. Could you explain your setup please?
 
I was thinking more along the lines of acceleration and more importantly braking. The cruisers across the pond have an identical payload capacity from what I can find.
 
You must log in or register to reply here.

Share this page

Back
Top Bottom