2021 Chevrolet Suburban High Country

GM’s new electrical architecture brings 5X more data-processing muscle than the previous trucks.

The Chevrolet Suburban (pictured) and its GMC Tahoe cousin are totally redesigned for 2021 with larger dimensions and upgrades including a new vehicle electrical architecture. (GM)

GM engineers tell me that their latest full-size light truck program, which most recently spawned the 2021 Chevy Suburban and GMC Yukon, encompassed nearly 10,000 engineering and technical staff during the peak of product development. I don’t doubt that, given the deep list of architectural changes and features designed into these all-new 3-row full-size SUVs.

For the 2021 Suburban, new truck-based architecture brings more than 4 inches of added wheelbase. (GM)
GM fullsize SUVs’ new architecture includes an independent rear suspension. (GM)
The optional 3.0-L inline six-cylinder diesel for GM’s 2021 fullsize SUVs is a class exclusive. (GM)
2021 Chevrolet Suburban cabin can be a plush and tech-laden as any luxury-make flagship. (GM)

Everything about the 4WD High Country Suburban I tested recently is big, with a 4.1-in. (104-mm) increase in wheelbase and a bit more than one inch stretch in overall length that gives second- and third-row seat passengers each an additional two inches of leg room. There’s also nearly two more cubic feet of cargo volume behind the back row, and those two seating rows now fold flat for optimized loading. All are significant improvements for those who use their vehicles as intended.

GM’s first (and some would say late) application of independent rear suspension to these vehicles is a ride quality improvement, in my subjective view. My test vehicle ($84,545) included standard magneto-rheological dampers, combined with an optional adaptive/load-leveling air-ride system ($1,000) that kept excess body motions well under control on my favorite stretch of potholed Michigan road.

Program engineers sweated the details making each of the Suburban’s electrically-actuated features (seats, mirrors, etc.) “industry best” in smoothness and quiet operation, in my view. There’s a segment-first diesel (460-lb-ft/623-Nm) 3.0-L inline-six and too many other changes, bells and whistles to note here. An invisible technical upgrade is GM’s new electrical architecture that brings 5X more data-processing muscle than the previous trucks, with over-the-air update capability.