Zac Quinn 
It’s no secret that the 2024 GMC Sierra HD will be getting an off-road focused AT4X trim level, with spy photos being a superb indicator for this. A dinged-up prototype for the new off-road variant was recently spotted by GM-Trucks.com, giving us another look at the vehicle and more details regarding the underbody. Below are our observations on the upcoming Sierra HD AT4X.
2024 GMC Sierra HD AT4X Prototype: Details
The spy photos give a great angle enabling us to see the skid plates and suspension elements applied to the rugged truck, and confirm our initial report that GM is expanding the ZR2/AT4X-spec capability into the HD truck space. The 2024 GMC Sierra AT4X features 35-inch Goodyear MT tires, as well as a minimalist front bumper that exposes a new front skid plate while improving the approach angle.
The GMC Sierra HD AT4X prototype in question doesn’t feature any running boards, and it looks like it also doesn’t have any rocker guards to protect the sides from damage – perhaps GM is leaving room for an AEV package akin to what was just announced for the 2023 Sierra 1500 AT4X. It’s clear this prototype has taken a beating on whatever trail it was taken, as visible damage has been done to the rear door, and the integrated step at the start of the bed has been pushed upward. Luckily, the underbody protection seems to have done the job and protected the essential components under the truck. Suspension-wise, the Multimatic DSSV dampers are either darkened out – they’re usually a golden color – or GM is testing another setup. However, the latter seems unlikely, as sources indicate that the 2024 GMC Sierra HD AT4X is already predestined to have a Multimatic set of dampers, just like the smaller Sierra 1500 AT4X and newly announced 2024 GMC Canyon AT4X.
The reveal of the 2024 GMC Sierra HD AT4X has to be close. And with the return of the Detroit Auto Show after a two-year hiatus happening in mid-September, we may see it then. If not, there’s the Overland Expo East in Virginia happening between October 7-9. Considering GMC’s increased presence with Overland Expo, it’s likely we could see the new truck there.
