2026 GMC Yukon XL AT4 Ultimate: Marion Buyers Guide

The off-road trim that doesn't ask you to give up comfort

AT4 Ultimate exists for a specific kind of buyer: someone who wants AT4's genuine off-road hardware but isn't willing to trade away the tech and comfort that come with Denali. The 6.2L V8 replaces the 5.3L as AT4 Ultimate's base engine outright — not an option, a standard swap — which brings 420 horsepower and 460 lb-ft to a trim that already carries AT4's skid plate, recovery hooks, and all-terrain tires. Air Ride Adaptive Suspension is standard here too, which matters on a vehicle this size: it can raise for ground clearance on a rough forest-service road and settle back down for a smoother highway ride between McDowell County and Asheville.

Super Cruise, GMC's hands-free highway driving system, comes standard on AT4 Ultimate with a 3-year OnStar One plan bundled in — a genuine value difference from AT4, where it's an option buyers have to add. Inside, Obsidian Rush full-grain leather with AT4 Ultimate-specific badging, 16-way power front seats with massage, and an 18-speaker Bose sound system round out a cabin that reads more like Denali than like a stripped-down trail truck. AT4 Ultimate seats seven rather than eight, since it swaps the standard three-across second-row bench for captain's chairs as part of the package.

What buyers say about upgrading their GMC

Buyers stepping up to a higher Yukon XL trim at Jim Cook GMC consistently mention the same combination of straightforward pricing and a team that stays reachable after the sale. Debra B. wrote: "Great customer service! Josh is a great salesman, Allen excellent at finance! Would definitely buy another car here." Steve B., a repeat customer, described the pattern across multiple purchases: "Everyone was very helpful and had one goal, customer service. Hard to find a dealership like this one anywhere. Great job, extremely happy. Third car I have purchased from [Jim Cook GMC]. Excellent service as always, ready as promised."

Frequently asked questions

What's the real difference between AT4 and AT4 Ultimate?

AT4 Ultimate's standout additions are a standard 6.2L V8 (versus AT4's standard 5.3L), standard Super Cruise with a bundled 3-year OnStar One plan, standard Air Ride Adaptive Suspension, and a full leather interior upgrade with massaging front seats. All three of those are options a buyer can add to a regular AT4 individually, so the Ultimate trim is essentially the pre-packaged version of a heavily optioned AT4, priced accordingly.

Does AT4 Ultimate seat 8 people?

No, it seats seven. AT4 Ultimate and Denali Ultimate both replace the standard three-across second-row bench with captain's chairs as part of their standard configuration, which drops max capacity by one compared to Elevation, AT4, and Denali.

Is Super Cruise worth having standard on AT4 Ultimate?

For drivers who spend real time on I-40 between Marion and Asheville, or longer highway stretches beyond, Super Cruise's hands-free capability on compatible mapped roads is a genuine convenience feature rather than a gimmick. Whether it's worth the price difference between AT4 and AT4 Ultimate on its own is a personal call — a demo at Jim Cook GMC is the best way to judge it firsthand.

Test drive an AT4 Ultimate

AT4 Ultimate is a lower-volume trim and inventory can be limited at any given time. Check current stock at Jim Cook GMC, or compare it against standard AT4 to see exactly what the Ultimate package adds.

All 2026 GMC Yukon XL guides

• 2026 GMC Yukon XL trim comparisons
• Yukon XL Elevation
• Yukon XL AT4
• Yukon XL Denali
• Yukon XL AT4 Ultimate
• Yukon XL Denali Ultimate
• Yukon XL service & repair
• Yukon XL pricing & leasing
• 2026 GMC Yukon (standard wheelbase) buyers guide