Coil springs for AHC (3 Viewers)

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Spacer do make a big difference with Kings. Much more so than with stock AHC coils. If you'd like to max sensor lift. I would then add either 20mm or 30mm spacer, depending on your weight and height you'd like. Note: You can stack up to 2 spacer, according to manufacture.

I'd would consider LC T-bars, if you've added weight like with winch and skids with that bumper. LC T-bars may not let you drop to low, if not enough front end weight at stock height. With just an iron front bumper and stock height (~19 3/8"), LC bars likely not needed.

You'll get benefits from this set up.
1) With your new globes, you should be able to dial in frt Mpa as low as you like 6.9Mpa, or even lower and not max the T-bars. Rear pressure, depending on weight and which spacer. You should be able to get ~6Mpa (before adding gear & people).
2) Reducing the pressure, by shift more weight to coils and T-bars. Will save AHC for when needed.
3) If AHC failure happens on the trail, you'll not drop to the rocks w/LC t-bars. (Carry a 30MM socket in your tool kit).

Note:
We set pressure and height, with full tank of gas and vehicle empty (no people or gear). You can play around a bit loading gear and checking pressure. Some do like to set pressure a bit on low side, unloaded. So that when loaded pressure aren't to high. It get into feel of the ride.
Great info, thanks for your help! After dialing down my sensor lift from max height to mid-way, my front pressures were low. After adjusting t-bars again I am at 6.9 front and 6.9 rear. This is with a full tank of gas, no passengers, on level ground. I have not unplugged the temp sensor for rear pressures, as I heard it was hit or miss. I am thinking the rear 30mm spacers combined with my King springs could get me to the proper rear pressures from my current 6.9. Thoughts or ideas? I will definitely look into the LC t-bars also but I am a little nervous as my driver side t-bar adjustment is a real pain to turn now. It doesn't appear to be cross-threaded but it is not easy to turn like the passenger side.

Rig is heavy for sure, build thread is: Cream Puff Build Thread - https://forum.ih8mud.com/threads/cream-puff-build-thread.1011395/

ARB front with winch, BIOR rear with tire carrier and hi-lift. Also have a spare in stock location for my trailer. Fridge stays in full-time and looking at doing a single drawer on driver side. So yeah, I got all the weight! That said I don't really need a max sensor lift, so moving that down a bit is fine.
 
Great info, thanks for your help! After dialing down my sensor lift from max height to mid-way, my front pressures were low. After adjusting t-bars again I am at 6.9 front and 6.9 rear. This is with a full tank of gas, no passengers, on level ground. I have not unplugged the temp sensor for rear pressures, as I heard it was hit or miss. I am thinking the rear 30mm spacers combined with my King springs could get me to the proper rear pressures from my current 6.9. Thoughts or ideas? I will definitely look into the LC t-bars also but I am a little nervous as my driver side t-bar adjustment is a real pain to turn now. It doesn't appear to be cross-threaded but it is not easy to turn like the passenger side.

Rig is heavy for sure, build thread is: Cream Puff Build Thread - https://forum.ih8mud.com/threads/cream-puff-build-thread.1011395/

ARB front with winch, BIOR rear with tire carrier and hi-lift. Also have a spare in stock location for my trailer. Fridge stays in full-time and looking at doing a single drawer on driver side. So yeah, I got all the weight! That said I don't really need a max sensor lift, so moving that down a bit is fine.
I'd reduce rear height (lower sensor), to reduce rear Mpa to 5.6Mpa. Than determine if you like that height or would like rear higher. If you want it say 10mm higher. Look to see if sensor will slide up ~10mm. If so add 10mm spacer. Than raise rear (sensor lift) about 10mm. These are approximate measurement, and will give you end results you'll need to tweak a bit. You may find 5mm or 20mm lift suits you better. However much lift from the 5.6Mpa you like, install same width spacer. Than adjust sensor again, to get the 5.6 to 6Mpa are good targets. You can also load with gear, and look at pressure. If this rig used 70, 80, 90% off road loaded with gear. You can drop sensor a bit, to lower pressure when loaded. But unloaded it will be a little stiff and lose dampening if Mpa to low. Play with it all you like. Get to where it feels good to you. Just don't run in to high a pressure, or you reduce life of globes and ride may get to bounce. May even kick off ABS system (TRAC off alarms). Push pressure to high, and system will fail to raise or go into fail safe.


T-bars:

The left side of 100 series, is heavier. So LH T-bars is always cranked more CW turns than RH. It's the LH T-bar adjuster, that get maxed in heavy built rigs. Make sure threads of T-bar adjusters are clean and add some oil to threads. When cranking on T-bars, make sure to put AHC into H first or lift front end with a jack. This helps reduce weight on T-bars, make easy to crank on T-bars adjusters. I use either a 1/2 ratchet. Or if a hard tuning adjuster bolt. I use q 3/4" breaker bar w/30mm socket

We both mentioned re-indexing the t-bars. To be clear: I'm not talking about CW or CCW cranks on adjusting bolts of t-bar. I'm talking about removing T-bars and re-setting off factory index points, to get more CW turns on adjusting nut. I've never actually tried this. I've always worked to index on the marks factory or after-market t-bars give us. Matching into factory marks of each mounting bracket.

I'd wait to see how system performs, once you have desired height & pressures in front also. If than you find your maxing the LH T-bar, and system has difficult raising. Consider the LC bars. Especial if at only 3/4" rake and can't get pressure down to ~6.9Mpa. I'd add LC T-bar if with 7/8" rake I couldn't get to ~6.4Mpa. With the LC T-bars. You'll find adjuster will have lost of thread (adjustment) remaining and easier to crank on.

LC T-bars work very well. Allowing full AHC L to H, and good dampening. In heavy built rigs. i.e iron bumpers, winch, iron skids, bell pan, sliders, roof rack, frig, etc.
They may not allow AHC into L, with only and iron bumper and sliders. This may not enough weight, even with max sensor lift.
For heavy built off roads. LC T-bars are a must, to keep off the rocks IMHO!

Once set up, put a few hundred or thousand mile on it. Than adjust again. It will likely change. As system settle in and you've tweak it a few times. Each time you find setting changes less and less.
 
I live in my Land Cruiser full-time, when I was building it for this purpose I did it with an eye on the Max Gross Weight, which is approximately 7,000 lb.

I discovered that at this weight my pressures were way too high. Even with King Springs and 30mm Slee spacers, so I replaced the globes and flushed the fluid, that helped quite a bit. But I was still at about 6.9 in the front and 7.5 in the rear.

So yesterday I made the next step of installing non-AHC torsion bars, non-AHC springs, and replacing the rear shocks (mostly because they were rusted) and I wanted to report that it's a smashing success.

The ride quality has not been affected at all, my pressure's in the front are 6.3 and my pressure is in the rear are 6.6. After cross leveling, I have almost exactly 19.5' in the front and 20.5' in the rear. With 14 graduations in my AHC fluid reservoir.

The torsion bars and springs are actually fairly easy to come across because everybody who has a 2000 through 2005 Cruiser has upgraded from their OEM bars and springs. If you go to any Land Cruiser shop that's mentioned in these forums they will probably just have them laying around.

So in short, for very little cost, I was able to upgrade my 2006 to be able to carry a 7000 lb load and still enjoy the ride quality the ahc system provides.
 
Yep, I am running non-AHC LC100 springs in the rear for the last 8 years.
I need to check my pressures again, but I took 30kg of AGM battery out of the front and put a 13kg lithium in the rear.
 
Has anyone already asked? What's the difference between AHC and non-AHC springs? I just fat-fingered an order for AHC when I meant to order non-AHC. Will they be softer/shorter or the opposite?

48231-6A770--rear RH AHC
48231-6A780--rear LH AHC
48231-6A680--rear RH non AHC
48231-6A690--rear LH non AHC
 
Has anyone already asked? What's the difference between AHC and non-AHC springs? I just fat-fingered an order for AHC when I meant to order non-AHC. Will they be softer/shorter or the opposite?

48231-6A770--rear RH AHC
48231-6A780--rear LH AHC
48231-6A680--rear RH non AHC
48231-6A690--rear LH non AHC
You're going to need to adjust your order, the ahc springs are significantly weaker than the standard springs.
 

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