Is suspension the only thing affected by extra weight?
New springs and shocks are only part of the equation. What about all of the suspension components (control arms, spindles) and their bushings? What about steering components? What about the braking system? What about body mounts (not just the rubber parts, but the actual steel perches)? What about the actual frame and additional torsion and stress? What about the drivetrain?
Just because our federal and state safety regulations don't keep tabs on personal vehicle weights after their, sold doesn't mean that we can ignore it.
Here's some additional info.
What’s in a name? A lot, actually.
www.thedrive.com
This is helpful, too, even if geared toward Aussies:
GVM Upgrades | ARB Old Man Emu 4X4 Suspension - https://oldmanemu.com.au/products/gvm-upgrades/
A good follow-up question to them would be: how are GVM upgrades different from just new shocks and springs?
It's good to see a max GVM upgrade that they can provide a 2015+ LC 200 as 4015 kg (8850 lbs), but if I was the fella at 8,600 lbs I'd want to know what else I'd need to do to keep my vehicle safe at those weights.