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AHC for off-road

Hutton

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Is AHC suspension ok for going off-road? Would like to hear from members who have gone off-road with standard suspension.
 
Is AHC suspension ok for going off-road? Would like to hear from members who have gone off-road with standard suspension.
I will amend my original statement.

Is the Pope Catholic ?
 
When you say "standard suspension", I suppose you mean conventional suspension, not AHC?
There isn't much input from those drivers in this thread so far. I suppose they don't regard the AHC as suitable for offroading.

There are both benefits and drawbacks. It is nice to have the car at a normal height for driving on road, keeping the CG low for stability, and then be able to lift it by 2-3 inches when needed. With a conventional you have to be lifted all the time. It is also nice to be able to lower it for gran to get in, but that is hardly offroadability.
It is also a benefit with AHC that the damping is adjustable and adapting - Wonderful floating over corrugated back roads. The AHC has to be maintained tho', just like any suspension system. If your pressure gets too high, it will not manage to lift you when needed the most.
Then the drawbacks: AHC means another possibility for failure, as the hydraulic part and the sensors are in addition to the parts of a conventional suspension. It is also a bit less Field Serviceable than plain mechanical parts. As long as the pipes and hoses are good, the hydraulics are pretty bomb proof, but it is still another layer of things that can go wrong. The cables and linkages for the height sensors are more prone to damages when offroad. E.g. on a perfectly good forrest road, I had a branch jumping up, bending the link for the rear sensor. My tail was suddenly scraping the ground, nearly. Not difficult to fix, but still, it's not a good situation a long way from home.
Still, I love the AHC, and think that the benefits outweigh the drawbacks, as least since I don't go offroad much and can maintain it myself. I do drive winding and corrugated roads, and often in snow. 2 inches up is often enough to get unstuck in the snow. If I was crossing Africa or something, I would not want the AHC as an extra source of trouble.
 
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When you say "standard suspension", I suppose you mean conventional suspension, not AHC?
There isn't much input from those drivers in this thread so far. I suppose they don't regard the AHC as suitable for offroading.

There are both benefits and drawbacks. It is nice to have the car at a normal height for driving on road, keeping the CG low for stability, and then be able to lift it by 2-3 inches when needed. With a conventional you have to be lifted all the time. It is also nice to be able to lower it for gran to get in, but that is hardly offroadability.
It is also a benefit with AHC that the damping is adjustable and adapting - Wonderful floating over corrugated back roads. The AHC has to be maintained tho', just like any suspension system. If your pressure gets too high, it will not manage to lift you when needed the most.
Then the drawbacks: AHC means another possibility for failure, as the hydraulic part and the sensors are in addition to the parts of a conventional suspension. It is also a bit less Field Serviceable than plain mechanical parts. As long as the pipes and hoses are good, the hydraulics are pretty bomb proof, but it is still another layer of things that can go wrong. The cables and linkages for the height sensors are more prone to damages when offroad. E.g. on a perfectly good forrest road, I had a branch jumping up, bending the link for the rear sensor. My tail was suddenly scraping the ground, nearly. Not difficult to fix, but still, it's not a good situation a long way from home.
Still, I love the AHC, and think that the benefits outweigh the drawbacks, as least since I don't go offroad much and can maintain it myself. I do drive winding and corrugated roads, and often in snow. 2 inches up is often enough to get unstuck in the snow. If I was crossing Africa or something, I would not want the AHC as an extra source of trouble.

Many thanks for this great reply. Much appreciated.
 
When you say "standard suspension", I suppose you mean conventional suspension, not AHC?
There isn't much input from those drivers in this thread so far. I suppose they don't regard the AHC as suitable for offroading.

There are both benefits and drawbacks. It is nice to have the car at a normal height for driving on road, keeping the CG low for stability, and then be able to lift it by 2-3 inches when needed. With a conventional you have to be lifted all the time. It is also nice to be able to lower it for gran to get in, but that is hardly offroadability.
It is also a benefit with AHC that the damping is adjustable and adapting - Wonderful floating over corrugated back roads. The AHC has to be maintained tho', just like any suspension system. If your pressure gets too high, it will not manage to lift you when needed the most.
Then the drawbacks: AHC means another possibility for failure, as the hydraulic part and the sensors are in addition to the parts of a conventional suspension. It is also a bit less Field Serviceable than plain mechanical parts. As long as the pipes and hoses are good, the hydraulics are pretty bomb proof, but it is still another layer of things that can go wrong. The cables and linkages for the height sensors are more prone to damages when offroad. E.g. on a perfectly good forrest road, I had a branch jumping up, bending the link for the rear sensor. My tail was suddenly scraping the ground, nearly. Not difficult to fix, but still, it's not a good situation a long way from home.
Still, I love the AHC, and think that the benefits outweigh the drawbacks, as least since I don't go offroad much and can maintain it myself. I do drive winding and corrugated roads, and often in snow. 2 inches up is often enough to get unstuck in the snow. If I was crossing Africa or something, I would not want the AHC as an extra source of trouble.
So, it boils down to, "Horses for Courses"
 
Is AHC suspension ok for going off-road? Would like to hear from members who have gone off-road with standard suspension.
Here is an artical from IH8MUD posted way back in Oct 2013, entilted
LX AHC Off Road Suitability

credit to TeCKis300

AHC gets a bad rap from most on these boards. While some of it is deserving, as it's a potentially expensive wear item to maintain and repair, most of the other reasons are largely undeserving as it's a robust and capable system that is meant to increase the capability breadth of the vehicle without compromises. That is, it will do very well for on road manners, yet also provide clearance, articulation, and active dampening when the going gets rough.

I can't find it at the moment, but Toyota had a diagram that compared the capability of AHC vs non-AHC equipped hundy. It basically showed the AHC vehicle having more capability and on and off road. Now you can't have everything and eat your cake too, as the obvious trade-off is increase cost and complexity. Which brings me to my main point.

Half of the negativity against the system is due to second hand owners unwilling to cough up to maintain and repair what is ultimately a wear item. Not that it's not durable as there are plenty of anecdotal stories about it lasting over 200k. The other half is due to second hand owners trying to modify the system, or use it outside of its carrying capability, without truly understanding how to modify it to do whatever they are doing. Then they blame any fault on some contrived incapability or unreliability of the system.

Fact is, it's a tremendously capable system that can allow you to have the best of both on road and off road qualities (unlike an off road oriented suspension which biases the truck). I'll list a few.

1) By it's very nature of having a large fluid volume, it has more thermal capacity than any remote reservoir setup - great for those washboards.

2) The suspension is ACTIVE, so it has the ability to automatically dial in the right dampening for any particular wash board and load.

3) AHC will RTI higher (toyota supported fact) due to its smaller anti-roll bars and active height control.

4) AHC is constant height, regardless of load within its rated capacity. For example, if you toss in 4 people and gear on a standard non-AHC hundy, you'll already begin at a lower ride height relative to the AHC equipped hundy. Nevermind that the AHC can lift on demand.

5) AHC can have more lift than a statically lifted (stock non-AHC shocked) hundy on demand. Because the non-AHC truck has to compromise to leave some droop in it's setup. The AHC can go even beyond its on demand high position, when the ECU detects the need.


Sorry for my long winded reply, but I hate watching the herd mentality (eg. above) bash AHC on these boards , without a substantive reply.
 
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Yes, pretty good tbh.

I was stating that on the standard AHC suspension, (with only K02 fitted) I think it’s great off road. Not driven one with anything else for comparison though.
 
Most 100s in the uk are AHC so that's why they just said yes.

Not used the AHC on a 100 but air suspension

So I find the adjustability great and is used a fair bit for getting under stuff and picking trailers.

Over rough terrain it makes a massive difference
 
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