When families need a vehicle that can provide massive storage space, ample power, and supreme comfort, a sacrifice needs to be made somewhere, and it's usually on fuel economy. But not with the 2023 Chevrolet Suburban. This is a vehicle with gargantuan proportions, up to 460 lb-ft of torque, and available air suspension for supreme comfort, so it checks all of the boxes for a large family road trip vehicle.

With both of the available V8 engines barely getting 20 mpg on mainly highway driving cycles, that practicality is offset by poor fuel economy. But Chevy also offers this SUV with a Duramax diesel engine that gets up to 27 mpg on the highway. To put that into perspective, that's the same fuel economy rating as the smaller Traverse with its V6 engine, and it's better than the Kia Telluride or Hyundai Palisade manage. In a vehicle this large, that's incredibly impressive.

CarBuzz spent a week driving the top-spec 2023 Suburban High Country with the Duramax engine to discover all the reasons why this is, in fact, the ultimate long-distance family cruise.

700-Mile Diesel Range

All of our past experiences with GM's full-size SUVs have been paired with either a 5.3- or 6.2-liter V8. The latter is a superb engine, but we wouldn't relish the fuel bill with only 16 mpg combined. Enter the 3.0-liter turbocharged inline-six Duramax diesel, an intriguing option for owners who plan to cover many miles. This engine is perfect for fleet customers (such as limo services) or anyone who travels frequently across multiple states with their family in tow.

It's available on all but the Z71 trim as either a $1,000-odd upgrade over the 5.3-liter V8 or a discount of between $1,500 and $2,825 compared to the 6.2-liter V8. On the High Country, it represents a $1,500 savings over the V8. Power is way down at just 277 horsepower compared to 420 hp in the V8, but the torque is identical at 460 lb-ft.

The trade-off in power is well worth it for the fuel economy, which is rated at 21/27/23 mpg city/highway/combined with rear-wheel-drive (one lower mpg per cycle with 4WD). In our testing, we saw up to 29 mpg on the highway in the 4WD model, so 30 mpg could be possible with 2WD. That suggests that if the stars aligned and you could cruise at a steady pace without any interruptions (and without having too heavy a right foot), you could theoretically drive for around 700 miles with a full 28-gallon fuel tank. Sadly, no one could manage that distance without needing a bathroom break.

Who Needs An Escalade?

Having driven every full-size GM SUV with the 6.2-liter V8, we feel qualified to say the Duramax diesel is a worthy alternative. No, it doesn't provide that sweet V8 growl, but the tremendous torque keeps it from ever feeling underpowered. And you may have a preconceived notion of diesel engines being loud and obnoxious, but this one is so quiet, it can hardly be heard at idle. As always, GM's 10-speed automatic transmission is a stand-out, delivering smooth shifts with no awkwardness.

As for the Suburban, it feels similar to its siblings, the GMC Yukon and Cadillac Escalade. The steering is precise enough for a vehicle this large, and the available Adaptive Air Ride Suspension ($1,000) soaks up bumps. This suspension builds on GM's already excellent Magnetic Ride Control and delivers superior comfort. The Yukon and Escalade offer more premium features, but after spending a week in the Suburban High Country, we would probably take the cost savings of the Chevy and treat our family to a nicer vacation. It's all the luxury a family needs.

Great New Technology

Last year, Chevy added its Google-powered infotainment to the Suburban and its smaller Tahoe Sibling. The base LS trim gets an eight-inch screen, but all other Suburban variants receive a larger 10.2-inch unit. Even this larger screen looks a bit diminutive sitting in the Suburban's expansive dashboard, but the graphics are clear and the user layout makes it easy to navigate with just a slight learning curve. Wireless Apple CarPlay and Android Auto are standard, and the whole system can be controlled by saying "Hey Google" followed by a voice command. It may not have the largest screen in the class, but this is among our favorite infotainment systems to use.

As with other GM vehicles, that screen provides up to 13 camera views, including a helpful trailer view. LT trims and above also benefit from a 12-inch digital gauge cluster. New for 2023, the Suburban can now be equipped with Super Cruise, GM's excellent hands-free driving assistance technology. If the impressive range didn't sell you on the Suburban's road trip pedigree, relaxing on the highway with no hands on the wheel should do it. We should note this is the latest version of Super Cruise, which can overtake slower traffic on the left and move back over to the right lane by itself.

Room For A Big Family

Even with the recent introduction of an extended-length Jeep Wagoneer L, the Chevy Suburban is one of the largest SUVs on the road and one of the premier family haulers. The High Country trim offers seating for seven with comfortable captain's chairs in the second row. Our tester came equipped with the rear entertainment system ($1,995) with dual 12.6-inch touchscreens, which offer Hulu and YouTube in addition to two HDMI ports for a gaming console or other device. We'd like to see full Amazon Fire TV integration with more streaming services, like Ford and Jeep offer, but this is still a pretty good way to keep the kids entertained over the miles between fill-ups.

We imagine your children will call dibs on the heated captain's chairs, but the siblings who get stuck in the third row still have a generous 36.7 inches of legroom (0.1 inches more than the Wagoneer L). They will even have access to their own cupholders, air vents, and USB-C ports back there.

Tremendous Cargo Capacity

Buyers who plan to use the third row often but still need space behind it for cargo will want to opt for the longer Suburban over the Tahoe. Space behind the third row grows from 25.5 cubic feet in the Tahoe to 41.5 in the Suburban. Only the Wagoneer L has more space behind its third row (42.1 cubic feet), but that's where the Jeep's advantage ends. The Suburban packs 93.8 cubes behind the second row (85.3 in the Jeep) and 144.7 with the second and third rows stowed (130.9 in the Jeep).

Storage space for the front passengers is generous, too, with ample door pockets, a wireless charging pad, and an electronically sliding center console with a hidden drawer.

High Country Price

The Chevy Suburban High Country is essentially a luxury SUV, and it comes at a luxury price. It starts at $80,445 with the more efficient diesel engine or $81,995 with the V8. As-tested, our Suburban checked in at $90,105 with options. Shoppers who can live without as many creature comforts can nab a Suburban LS with the Duramax starting at around $60k with 2WD.

GM recommends premium gasoline for its 6.2-liter V8, which costs around $4.235 on-average across the US. according to AAA data (as of this writing); comparatively, diesel costs around $4.676. We can't even attempt to calculate a break-even point here because the diesel engine is actually cheaper than the V8, meaning it will save you money instantly, and even more as you rack up the miles. In fact, by our quick calculations, in ideal circumstances, the Suburban could get across the entire United States using four tanks of diesel; sure, a straight-line cruise without stops or the nuances that affect gas mileage isn't likely, but it's still an impressive idea.

Ford and Jeep don't offer a diesel engine or anything that comes close to netting what we achieved on the highway in this segment. Combined with the Suburban's class-leading cargo capacity, excellent comfort, Cadillac-level luxury, and hands-free Super Cruise technology, it's easily the ultimate family road trip vehicle for under $100,000.