To anyone that has removed their AHC... (4 Viewers)

[Jrod]

I've got a few questions.

How did you manage to get the top bolt on the accumulators off (it goes into the top of the frame)? There's almost no room to get your hand and a wrench up in that area.

Did you remove all the hard lines, and wiring harness? I've gotten conflicting information on this - is the AHC wiring harness a stand alone harness that clips into the main harness?

Do the hard lines mounted to the frame come out without cutting them up?

I have the accumulators off the passenger side, and the driver side front, but I'm stuck on the canister, and driver side rear accumulator - I can't get to the top bolts and need your help.

Any input is greatly appreciated!

 

[Brock]

- I cant remember on top bolts but do remember were a pain in ass and took a while to get off
- yes removed hard lines and did most of them intact...only had to cut a few. since i was not interested in saving the parts I did not worry about destroying them...just make sure it is AHC lines and not brake or other before you start removing
- removed sensors and unclipped everything I could but left rest of wiring in place..did not cut anything
- only lines I cut for sure was the brass fitting for rear shocks...used air driven cutting wheel to get through the braided high pressure line they use and then tucked ends back into frame where they exited....most of this I think is in my build thread.

 

[pcut]

Call Slee and ask anyone there- they've done a ton of these!

 

[Jrod]

Call Slee and ask anyone there- they've done a ton of these!

A word to the wise - I can't speak for Slee specifically, but don't call a shop and expect to get help working on your own vehicle. I called a recommended shop just to ask a question and got reamed for doing this.

 

[Warrenpfo]

I did mine only a few weeks back so it’s all very fresh in my mind.
You need a 10mm flex head ratchet spanner and for some of the top bolts you are working blind so small hands does help quite a bit.


I also used a 10mm socket set (smallest you have with as little play in the mechanism helps as on some you only able to get 1mm of a turn at a time to start.

I removed absolutely everything associated with the AHC over a weeks’ time working in the evening.

Make sure you have removed as much of the fluid as you can and then start in the engine bay. Being a European car it may be the opposite for you but on mine on the driver’s side (RH) you have the height sensor with a tail plugged into a wiring harness that runs the length of the chassis rail to the rear shock.

You also have the AHC line that runs to the accumulator bolted on the chassis rail which then runs up and over the prop shaft to the other side where there is a manifold.

Staying on the driver’s side you have the rear height sensor, just the one rather than one per shock as on the front.

You also have the AHC line that runs to the accumulator for the rear and then up and over to the manifold on the other side.

There is also the wiring harness that runs all the way to the front held in by clips that I just removed.


I used tin snips which made removing the lines very easy as there is no way in hell I would ever re install the AHC system and it sped up the process by a good few hours. The lines are held in place by clips that I also unbolted.

On the other side you have the same up front but also the pump and reservoir to remove that then has lines that run down to a solenoid valve along with the front height sensor and line from the front shock to the front AHC.


The same also happens on the passenger side as the drivers with the wiring harness.


The only difference is there is the high pressure pump assembly to remove and the manifold held on by 4 bolts.


My brake line to the rear runs the same side as the manifold so double check which lines you are cutting.

Anything else I can help with just shout.

 

[Jrod]

I did mine only a few weeks back so it’s all very fresh in my mind.
You need a 10mm flex head ratchet spanner and for some of the top bolts you are working blind so small hands does help quite a bit.

I also used a 10mm socket set (smallest you have with as little play in the mechanism helps as on some you only able to get 1mm of a turn at a time to start.

I removed absolutely everything associated with the AHC over a weeks’ time working in the evening.

Make sure you have removed as much of the fluid as you can and then start in the engine bay. Being a European car it may be the opposite for you but on mine on the driver’s side (RH) you have the height sensor with a tail plugged into a wiring harness that runs the length of the chassis rail to the rear shock.

You also have the AHC line that runs to the accumulator bolted on the chassis rail which then runs up and over the prop shaft to the other side where there is a manifold.

Staying on the driver’s side you have the rear height sensor, just the one rather than one per shock as on the front.

You also have the AHC line that runs to the accumulator for the rear and then up and over to the manifold on the other side.

There is also the wiring harness that runs all the way to the front held in by clips that I just removed.

I used tin snips which made removing the lines very easy as there is no way in hell I would ever re install the AHC system and it sped up the process by a good few hours. The lines are held in place by clips that I also unbolted.

On the other side you have the same up front but also the pump and reservoir to remove that then has lines that run down to a solenoid valve along with the front height sensor and line from the front shock to the front AHC.

The same also happens on the passenger side as the drivers with the wiring harness.

The only difference is there is the high pressure pump assembly to remove and the manifold held on by 4 bolts.

My brake line to the rear runs the same side as the manifold so double check which lines you are cutting.

Anything else I can help with just shout.

Great post - thanks!

 

[r3run33]

How did you guys get rid of the codes after the AHC removal?

 

[Jrod]

How did you guys get rid of the codes after the AHC removal?

Codes? I pulled the fuses and unplugged the AHC computer.

If you're getting the VSC code you need to put the 20 amp fuse for AHC back in.

 

[Brock]

As Jrod said...you will get no codes except possibly the VSC and Steering Angle code...put fuse in footwell for AHC back in as it powers the sensor for steering angle. Then no codes and all you will be left with is possibly the flashing AHC light that says OFF. Mine is still flashing after more than a year...does not bother me enough to tear apart the dast to cover it up with black tape or pull the bulb.

 

[r3run33]

i don't have any codes throwing yet because I have not done the swap out yet; I spoke to Slee and he said he would take care of the codes. A VSC code would concern me; no one else thinks that????

 

[Brock]

yep that is why I plugged that fuse back in immediately after removing. I would rather have full use of VSC than not.

 

[cruiseroutfit]

Some more tech on removing the rear shocks:
https://forum.ih8mud.com/100-series-cruisers/642688-need-help-removing-ahc-rear-shocks.html

You can do a minor AHC removal which is capping the lines on the frame and removing everything else including the fuse/relay to keep the lights off the dash. Its also entirely possible to remove 100% of the AHC components but its a much more in depth project.

 

[Wilsil]

Interesting read guys.
I feel an AHC removal coming up, but need some more reading first.

 

[Surfy]

Why you want to take out the AHC?

I do a transafrica with it (Land Cruiser 200 V8 Diesel, Europe Spec) - loved the comfort and capability of the system.

It saved us severall times a lot of work, because the AHC can get higher as in height - when it detects wheelsping in 4LO.

Also you can avoid work, with set the settings to low - and fill stuff under your tyres - bevore you set it back 2 normal.

The AHC System lowers the Car on higher speeds - which helps to avoid some roll overs (how often we have to drive arround animals with 70miles - who jumped out of the bushes).

With a normal suspension with lift - we never would have the same amount of fun. And a lot of digging or winching more in sand and mud.

You have a streetcar on the highway and a capable offroader in bad terrain. You can adjust the dampers to get the optimal ride comfort - why you want to take it of?

You can also put in a stronger AHC Suspension like i did - when you add more weight. Is in your area nobody who understand the AHC System, and is able to adjust it this way you need em?

I cant believe that the Land Cruiser 100 AHC should be so bad, compared to the Land Cruiser 200..

Surfy

 

[Wilsil]

Hi Surfy,
The reason why I would replace it is the weight of the assoccories I will add to the LX470. Plus towing the camper trailer will drop the car into Low mode which isn't good.
Upgrading the AHC is possible but as the experts are saying is not worth the money as the system has done over 230,000 kms now and the components are gone out.
Replacing the AHC components is more expensive then replacing it will conventional suspension.

I agree with you that the AHC is great, as long as it is doing its job.

 

[Surfy]

Replacing the AHC components is more expensive then replacing it will conventional suspension.

I agree with you that the AHC is great, as long as it is doing its job.

Ok - that is reasonable.

My Landcruiser was stock 2.85 tons, and can legally load to 3.3to.

Our overlanding weight was near 4to (with 2 People, 280L Diesel, 85L Water, 33" spare tyre behind and all gear).

And the AHC had handled this easy, after the upgrade. We push often with 70miles on bad dirttracks - because the tracks was to bad to drive slower. And several times we had a short flight - because of some hidden jumps on the track.

So i was wondering - why others try everything to take out their AHC - also on newer cars - this is one of the best steps of engineering in the last years - when you ask me.

 

[Wilsil]

True but it is also very hard to repair in the bush.

 

[Surfy]

True but it is also very hard to repair in the bush.

You can replace the shocks with normal ones - and can drive away. You will have some "errors" - but you can solve it in the next big city.

Most other parts on the car make more headache when they stop working. The engine, the alternator, the waterpump - i never thought an instance about the suspension But anyway - i am not able to repair any of the stuff For me it is hard to change a tyre, and a challange to change the fuelfiltre.

Surfy

 

[l3n0x]

Does anyone know how to remove the AHC pump assy?

 

[PAFJ]

Does anyone know how to remove the AHC pump assy?

The reservoir/pump assembly? If so, there are 3 nuts in the fender well and 1 in the engine bay that secure it in place.