Either you're looking for:
- more lift
- more weight capacity
- a less costly and more reliable suspension system
I'll also point out that some people don't like the feel of the AHC system vs. conventional suspension.
As far as lift, if you want permanent lift beyond what AHC can give you, you'll need to swap out the suspension.
As far as weight capacity if the vehicle exceeds a certain limit (can't remember for sure but something like 600 lbs cargo plus full car of people or something) then it goes into limp mode (L for Low or Limp
). Now imagine someone with heavy front and rear bumpers, drawer systems, people in the car, gear etc. they will easily exceed the weight capacity and then the car stays in L 'cause it can't lift beyond that. Obviously if you're in that situation you'll want to either swap out the suspension, swap out the springs and fool the system (think it's been documented here how to do it), or use an air bag to support the additional weight.
As far as reliability and cost of the AHC system - the parts are all ungodly expensive, it can be tricky to diagnose, it requires special tools and expertise to diagnose the system, so most shops end up throwing parts at any problem and you easily end up shelling out wads of cash (2k+ easy) to fix problems. Just some examples - there are 4 accumulator globes and each costs $500 for the cheapest possible price on OEM parts (dealers will easily markup and charge 600 ea.). There are 3 height sensors, think their cheapest price is ~300 each. The pump and motor assembly as a unit is ~2k (pump alone is only like 250 i think), each of the 5 accumulator assemblies is ~500 (not the accumulator itself but what the accumulator attaches to - think it's referred to as the actuators), there are tons of expensive hoses (hundreds of bucks for some of the individual hoses), the shocks, springs, miscellaneous parts and electronics. So add all that up and we're talking WELL over 8k not including labor (total cost of suspension). There are horror stories of people spending 4k+ to repair their AHC. If one has a trusty mechanic or can do it themselves they can save tons of dough, but it still can be time consuming and downright frustrating to troubleshoot some of the issues. Most every one has an issue with their AHC at some point in time over 100k - whether it's a height sensor gone bad that causes the rear end to jack up to heaven or a tilt to one side, or won't raise or lower (the fluid won't operate properly below certain temperatures - a friend of mine had that problem and the dealership had him replace all the height sensors - I strongly suspect it was just the temperatures as he was in canada in -40 weather). So it's super friggin expensive once you need to start replacing things, it's complicated which means labor is super expensive and you may spend lots to fix a problem, and arguably it's not as reliable, and certainly not as easy to repair/maintain off road as a classic suspension so I think you could end up more likely with a catastrophic failure than a classic suspension.
I'm sure you already understood that for lift or weight capacity (i.e. hardcore) you would want to swap out suspensions. The part that might have been more elusive is that people get fed up with the cost and frustration of maintaining the system. From what I see, aside from lift or weight issues, people usually consider the suspension swap when they're at the fork in the road -> ~100k miles and they find out they need new accumulator globes and they're facing 2k minimum for the OEM globes on the one hand or <800 parts for a reliable, rugged, simple suspension replacement on the other (whether that's OME, Bilstein, or OEM LC). For many people it's a no brainer after one or more parts of their AHC fails.
