AT4X HD Suspension Availability?

Does anyone know if/when the AT4X HD suspension will be available as a standalone purchase to upgrade, for example, a regular AT4? Asking for a friend who has some hardcore parking lot terrain to deal with...
I would not jump to it just yet. I'm still struggling with my 2024 Sierra 2500HD AT4X AEV Edition purchased less than a month ago and ride issues from day 1. GMC were no help. I changed all five tires at my own expense which somewhat improved the situation yet there is strange intolerable vibration coming up through the seats (likely suspension issues). I'm still trying to figure it out and now looking for a more sympathetic and intelligent dealer/tech who is familiar with this vehicle.
 

I would not jump to it just yet. I'm still struggling with my 2024 Sierra 2500HD AT4X AEV Edition purchased less than a month ago and ride issues from day 1. GMC were no help. I changed all five tires at my own expense which somewhat improved the situation yet there is strange intolerable vibration coming up through the seats (likely suspension issues). I'm still trying to figure it out and now looking for a more sympathetic and intelligent dealer/tech who is familiar with this vehicle.
Dang, sorry to hear that's happening to you. Super frustrating dealing with issues on a new vehicle. Is it only at certain speeds or does it happen at some level all the time?
 

It can happen at any speed on any road that's less than perfectly smooth and I dont mean dirt roads but freeways and almost perfect roads; the oscillations are not back to front or side to side but from bottom up equating to 3" bumps roughly twice per second and absolutely consistent. After a few minutes of that, one starts feeling sick.
We have several cars but this one was meant to be my pride and joy, my new toy I want to show off to friends and relatives, now I'm too scared to do that.
I think its something to do with the shocks, leaf springs or both.
 

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Get your tires Road Forced Balanced…I would almost guarantee it might be the rims and tire. I had a noticeable vibration in my new 24 AT4 HD. I took it to a tire shop and had all 4 tires road forced balanced and the rears were out big time. One was almost 50 ounce out and the other was 30 something..Took it to the dealer with the paperwork..the recheck all them and agreed to replace the one that was 50, but said the got the 30 down to 20 something and said it was acceptable. It had 7 gigantic weights to get it there and it still vibrated a little. I bought a new rear BFG AT3 for that one they so called balanced and now it drives good.…You may have a bad set of rims..road force balance will tell you that also. My truck had less than 500 miles when I went thru all that mess.
 

I had the original rims/tires road force checked by GMC and three were out of balance however GMC refused to replace any tires, even though they had just 300 miles on them from my drive home from the dealer in OR. GMC subsequently ran a picoscope test and said it proved it was not the tires. To validate that further they temporarily installed 20 or 22" wheels and tires from a different new GMC truck and the issue persisted and GMC denied all responsibility. I then replaced all five tires and balanced at my favourite tire shop, at my own expense with Mickey Thompson AT Baja Boss tires and the ride improved quite a bit but the issue did not completely go away. The vibration is so consistent when it happens, it goes right through my butt and up the body. It almost seems as if the drive shaft, or gear box or engine gets into an oscillating rhythm. I looked under the truck, its built like a tank, could not determine anything. I need to take it back to the dealer across the border in Langley, BC Canada, the only dealer near me who is better than most. I'm basically Stuck with this machine, now with over $133k into it; there has to be a solution.
The vibration is from the bottom up, the entire length of the vehicle bouncing all four corners at the same time and frequency, not from one corner, the front or rear.
It almost seems like the dssv multimatic suspension is compensating all four shocks at the same time; I need to check if I can disconnect any sensors, I know so little about this new truck, its not going to be easy.
 

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You might need to throw a standard set of shocks on it just to see if it’s your factory shocks causing the problem.…I hate throwing money at something just so you can pin point or fix a problem.
 

I looked at Bilsteins, I have Bilstein IRC (remote damping) shocks on my lowered Mercedes Benz and they are awesome; could not find anything for this new beast. I may have to try Rancho or something after I exhaust all other possibilities. I need to do whatever it takes to get out of this embarrasing position.
 

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